Great Orion Nebula Rises

The Christmas special is the Great Orion Nebula, photo of the holiday night, in a remarkable black & white astro imaging capture. The images show much more detail as the size of the telescope increases. This is a non-Amped image with M-processing by M. Otis.

Great Orion Nebula Rises

Winter is upon us as the Great Orion Nebula rises around sunset and is favorably placed in the East for this astroimaging result. M42 looks good in practically any telescope but the large ones show color and breathtaking views.

Going into color mode yields the result below. Which is preferred?

The final processed photo below accentuates the inner filaments of star bearing nebula deep within the bowels of this simple digital transformation.

Orion CT80 80mm (3.25") f/5 Doublet Refractor Telescope

Above: The Orion 3.25-inch doublet crown and flint coated lens refracting telescope is f/5 and can show large sky areas. With a 1-inch or 25mm focus eyepiece gives only 16 power. A half inch FL EP (12mm) or a 2x negative projection barlow takes it to 32x or a 3x to 48x. It can be used as an RFT rich field telescope, a finderscope, guider and tracker or a main telescope. A plastic finderscope with a dovetail mount will keep it lightweight.

Orion CT80 80mm (3.25") f/5 Doublet Refractor Telescope
I'm really excited about these small telescopes that are lightweight, easy to carry and transport, and only take moments to easily set up. The class of these telescopes include tiny Dobsonians, tripod mounted OTAs and OTAs that share resources mounted onto an existinging telescope - for example to take advantage of a GOTO mount. Some examples are the Orion f/5 3.25-inch diameter refractor with a 14.7-inch tube, and the Acuter 60mm f/12.5 Maksutov which is a mere 8-inches long with the star diagonal attached. The CT80 is 2.25 lbs and the Acuter Mak is only 1 lb.

Orion CT80
The Orion CT80 is a 3.25-inch diameter f/5 coated doublet achromat refractor OTA with a 400mm focal length. A 1-inch focus eyepiece will give about 16 power and a very wide view of the sky. The OTA has a dovetail mount for a finderscope, and up until this time it was unknown how to mount the OTA. Upon close examination today, the OTA has a photographic standard 1/4" hot shoe mount for attaching to a tripod. An HF-3110 long four level tripod was found in inventory to make this telescope complete at no extra cost.

Left: the Orion CT-80 OTA is seen mounted on the HF-3110 tripod. The OTA is a bit heavy for this lightweight tripod but still fully functional.

The CT80 will also attach to the Celestron Nexstar 6SE using the Celestron camera mount. The CT80 weight is listed as 2.25 lbs. The optics are coated crown and flint glass mounted in a metal tube with a rack & pinion focuser. The tube is 14.7-inches long. Resolving power is 1.45 seconds of arc. It's short FL low power makes a fine addition to the Nexstar 6SE long focal length Schmidt Cassegrain scope and it gets to share the GOTO mount.

Left: a finderscope is added to the OTA using ring mounts on a dovetail shoe. The finder is all plastic with resin lenses and extremely lightweight. The rings and dovetail mount are metal and much heavier than the finderscope. however, these are capable of maintaining the rigidity needed for holding precise calibration.

Without central obstructions compared the Schmidt Cassegrain design, generally refractors are said to be equivalent to a Newtonian reflector or catadioptric about double the aperture. In this case, the 3.25 becomes a 6.5-inch telescope. The CT-80 has potential as its own telescope, and when mounted on the Nexstar - a guide telescope or dual telescopes on the single GOTO mount. At f/5 it can give 16x with a 1" EP. Many of these small telescopes are used as the main scope in astro imaging. Note: the 3.25-inch CT80 refractor is larger than a Celestron 2.99" reflector Firstscope.

Above Left: The tripod is an HF-3110 which is at just the right height when used with a 90-degree diagonal, but ends up being a bit wobbly along the axes until properly adjusted with four adjustment points. After moving the telescope, doing focus, a fair amount of time is required for the vibrations to subside. If not for testing, temporary usage and the ultimate in lightweight tripods for transportation, a larger and more sturdy tripod is recommended. 

Log Saturday April 23 2022

Otis AstroImaging Log Saturday April 23 2022

NTO Nexstar Telescope Observatory
NTO is in operation. The refinement of the telescope platform is in progress. All parts and components for the platform are ready and waiting for assembly except the empty water bottles. Currently we have 15 bottles on hand. An order was placed for more water/bottles. The rate of collection is about 1 empty bottle per day. Some experimenting will determine the exact number needed. The bottle bases with the ability to withstand 1000 PSI each need to be placed in proper positioning on the back of the platform to conform with the steel rail.

Enhancements

TRANSDIGILOG - Transitional Digital & Analog

AMPING - Amplification of Telescope Diameter

TRANSAS - Transitioning Art and Science

NTO is fully operational with image processing and enhancements to include the new invented TransDigiLog. Combining a special transition of digital with analog, coined TransDigiLog, the process takes the best of both worlds - modern digital imaging and the foundations of spectroscopic emulsion based film. In this case, the spectroscopic film is transitioned to digital color, which never existed or was not popular during the original historical era of common astronomical spectroscopic usage in the early 1970s.  Also included with the newly added repertoire of power techniques for the Celestron Nexstar 6SE, invented by the author, is Amping. Amping takes a given telescope diameter and qualitatively gives it the appearance of an aperture 10 or 100 times larger. The third technique uses a combination of transitioning art and science, TransAS, to bring out highly specific features and renditions. The science side is highly quantitative while the artistic side is very qualitative in representations.

First Image Processing Result!

The first webpage with the first image processed and enhanced result, from the Celestron Nexstar 6SE telescope, was posted yesterday Friday April 22 2022. The invented technique by the author takes both digital and analog to create a new advanced and enhanced representation of the COSMOS that vastly outstrips the original in many technical aspects of imaging. This employs more than one method techniques application and of image processing. Additional processing is designed to remove light pollution, air pollution and upper atmospheric haze. The image is taken with a Celestron Nexstar 6SE telescope in the famous nebulosity area of the constellation Orion where stars are born and vasts wisps of bright red hydrogen atoms form clouds of interstellar gas filling the vastness of this region of space and time.

https://otisastro.blogspot.com/2022/04/astroimage-processsing-with-nexstar-6se.html

Unboxing the Orion StarBlast II EQ 4.5"

Unboxing the Orion StarBlast II EQ
Orion makes two different StarBlast f/4  4.5-inch diameter telescopes, the StarBlast and the StarBlast II EQ. The first sets on a modified Dobsonian mount, and the latter has an Equatorial mount and motor drive. Let's take a look at unboxing the the StarBlast Equatorial version, with the AstroTrack Drive.

The telescope is shopped in one box which is protected by another full size box. The assembled weight of the telescope is listed as 20.7 lbs. Inside are a series of smaller boxes fitting together like a jigsaw puzzle, each holding parts except one box which is an empty space holder. The parts and components were adequately protected for international shipping.

The telescope parts were set out on a round table and then sorted. Everything was present except for the printed manual - it was for another telescope. So I had no assembly instructions but assembly is so simple and easy that no instructions are needed. If instructions are needed, the pdf file can be downloaded at the Orion website or several videos from Orion are available on YouTube. 

In the Box

Orion 4.5" f/4.0 reflector telescope optical tube assembly

Orion AstroTrack Motor Drive

25mm Orion Sirius Plossl telescope eyepiece (1.25")

10mm Orion Sirius Plossl telescope eyepiece (1.25")

Tripod legs

EQ-1 equatorial telescope mount

EZ Finder II reflex sight aiming device

Collimation cap

Tube rings

Counterweight

Counterweight shaft

Tripod accessory tray

Slow-motion control cables

Latitude adjustment T-bolt

Orion MoonMap 260

Orion StarBlast Color

Orion StarBlast Color
The color of the new Orion StarBlast Dobsonian telescope is a remarkable story to behold

Many white OTA telescopes had flooded the market in the past and white became so common that many telescope makers began using alternate black color.

After a number of years of stumbling over and into black telescopes in the darkness of night, black was deemed no longer creative and Orion began looking for new colors of originality for the lineup.

Signature red was of course taken up by Edmunds red Astroscan telescope and Celestron made a popular line of orange Schmidt-cassegrain telescopes.

The most creative and unusual esteemed and royal colors were sought after and reviewed. Teal was a new web color formulated in 1987.

In the 1990's Teal was a cyan-green fad color for sports and it was adopted by many teams for the color of their uniforms. The color is believed to originate from the common Teal, a member of the duck family whose eyes are surrounded by this color.

Teal green is a darker shade of teal with more green and is a variable color averaging a dark bluish green that is green, darker, and stronger than invisible green or pine tree. Teal green is most closely related to the Crayola crayon color Deep Space Sparkle. Air New Zealand picked Teal green as their signature airline color.

In 2003, the California-based Orion Telescopes and Binoculars introduced the StarBlast, a 4.5-inch Newtonian reflector grab and go telescope with a Dobsonian mount. The telescope became popular with both kids and adults and even libraries have some for checkout. When Orion Telescope Company formulated the signature StarBlast OTA color, they went a step further than white or black and formulated metal teal pearl color. The tube finishes were embedded with scintillating sparkles of a metal appearance (a borrowed technique of creating finer car finishes).  Under certain lighting it looked like tiny pinpoint stars making up the tube finish, a fantastic and very original sight to behold.

Orion StarBlast Telescope Differences

Orion StarBlast Telescope Differences
The purchase was for two identical Orion StarBlast telescopes of 4.5-inch aperture at f/4. Only the mounts are different, so we thought. This page will describe the actual  differences between the two.

BIG BLUE
Nicknamed Big Blue because of its beautiful blue metal tube and larger footprint created by the mount style, this telescope is shown on the right in the photo. The Orion Starblast II EQ with motor drive has many obvious differences when compared to the Dobsonian mounted version. With a total weight of 20.7 lbs it comes with a German Equatorial mount and requires some assembly. A motorized clock drive moves the telescope in right ascension using one motion control knob and a single 9-volt battery. It also has manual slow motion controls for right ascension and declination. Setting circles are provided. Differences also include the primary mirror  - Orion specifications say it's made of soda lime plate glass. Also different are the two eyepieces, both Plossl design at 10mm and 25mm focus. The telescope comes with a Moon map. The product manual must be downloaded. Assembly instructions are in the manual or found on Youtube with Orion's video.

LITTLE GREEN

Nicknamed Little Green because of its beautiful green metal tube and small footprint compared to its sibling, this Orion StarBlast is Dobsonian mounted and is a true grab and go tabletop telescope. Weighing only 13 lbs., no assembly is needed. It sets inside the shipping box fully assembled. There is no motor drive. The primary mirror is made from low expansion borosilicate glass and the includes Ramsden eyepieces 6mm and 17mm focus. The entire telescope weighs only 20.7 lbs. and can be lifted with one hand. This is a grab and go tabletop telescope, setup and ready for action. It comes with a product manual, and Starry Night SE software.

ADDED DIFFERENCES

As of the date on this posting, Little Green gets a replacement Celestron 5x24 lightweight resin lensed finderscope to do star hopping. Big Blue gets a cell phone holder, Apple iPhone Max X, and Celestron software to do push go goto to find sky objects.

Orion StarBlast II Telescope Wins Red Ribbon Award

Orion StarBlast II Telescope Wins the Coveted Red Ribbon Award at Singularity Observatory
Ten telescopes were analyzed in twenty different categories and the Orion StarBlast winner took the coveted Red Ribbon Award

Telescopes reviewed were the (1) Celestron CGX/L 14-inch edge HD, (2) Celestron CGX/L 9.25-inch Edge HD, (3) Orion StarBlast Dobsonian, (4) Orion CT80 Refractor, (5) Celestron FirstScope Dobsonian, (6) Orion StarBlast II EQ, (7) Unistellar eVscope digital telescope, (8) Meade 60AT Refractor, (9) Celestron 9x50 refractor, 10) Meade ETX/90

It's agreed that analyzing a telescope may in part be directly dependent on a person's goal. For example, will the telescope go into a permanent observatory or is it designed as a lightweight grab and go scope? This contest is an overall average and an overview of the most likely and desirable key points.

The telescopes were rated in twenty categories, with ratings from 0 to 10 with 10 best. Points were added up and the telescope with the highest number of points is the winner.

1) Weight: easy to lift, carry

2) Size: ability to move through door, assembled

3) Portability

4) Setup time

5) Takedown time

6) Learning curve

7) Ease of use

8) Ability & ease of calibration

9) Number of defects: does it work?

0) Amount of time used

12)  Diameter: light gathering ability
13) Optical Quality

14) Rich Field Ability or Planets

15) Tracking ability

16) Grab and go

17) Convenience: power, computer, usb, cables

18) Cost

19) Availability

20) Support

Telescopes Analyzed

Celestron CGX/L 14-inch Edge HD

Celestron CGX/L 9.25-inch Edge HD

Orion StarBlast Dobsonian

Orion CT80 Refractor
Celestron FirstScope Dobsonian

Orion StarBlast II EQ
Unistellar eVscope digital telescope
Meade 60AT Refractor
Celestron 9x50 refractor
Meade ETX/90

The Winner: Orion StarBlast II EQ with Motor Drive
In summary, key award winning points and amazing features of the Orion StarBlast II EQ were ease of use, portability, light weight, easy to lift and carry, and with a very small learning curve. The telescope is easy to initially assemble, has a small footprint, fits through doors and inside cars when fully setup, and sports parabolic quality optics at f/4.

It's fast and large enough optics to show deep sky objects, setup and takedown time is either none or very fast and easy, no computer or AC electricity needed, it has good slow motion controls, and is good for astrophotography with a cell phone camera and camera mount. It can be used for lucky imaging with a CMOS camera, the scope and mount have a fast setup time of about 2 minutes or none at all.

The StarBlast telescope is low cost, has a one button motor clock drive, has calibration ability and is very easy to calibrate, it's supported by Orion, However availability is at high demand: I waited 2.5 years for new stock to arrive. The number of defects is 1 (locked on toe stopper). The PTA has rich field wide angle ability and is outstanding for the Moon, deep sky objects, and moons around planets, it's an excellent star hopper - it can upgrade to the lens-based Celestron finderscope with matching mounting bolts.

Orion has fast shipping, the telescope by choice is used very frequently, features include grab and go, German Equatorial with rapid takedown time, sets up in seconds with a compass, and this telescope has extra powers - the aperture is ideal for more seeing days due to its size, the primary has glass conducive to rapid cool down thermal, it sees better through window glass, and has adjustable secondary diagonal).

Included eyepieces are excellent. Focuser is tight and smooth. Upgrades with with a Bahtinov mask for achieving good focus, a front end full diameter specialty solar filter for studying the sun, and an iPhone for making a push to goto DIY finder. The telescope has many uses for many projects.

Orion StarBlast II EQ Telescope Assembly

The Orion StarBlast II EQ telescope arrives in kit form with these parts ready for assembly

Assembly of the Orion StarBlast II EQ Telescope 
The Starblast II EQ telescope is easily assembled by following these guidelines

Assembling the Orion StarBlast 4.5-inch equatorial telescope is routine for the most part. The kit comes with an assembled OTA optical tube assembly and the German equatorial head is for the most part ready for mounting. Unfortunately my telescope kit arrived without the instruction manual and therefore no assembly details were provided. Fortunately the assembly is very basic and straightforward and no instructions are needed when following a photo from online sources. For more details, Orion provides a YouTube video for assembly. The telescope manual is also found online in PDF format at a link on the Orion website.

The Chinese manufactured Orion StarBlast II EQ Equatorial Head is a marvel of exquisite engineering. It arrives with most of the main parts assembled.

I had no problems assembling the telescope kit - all the parts were present with no hardware missing. A wrench and screwdrivers are provided in the kit, however when it came time to assemble the tripod tray to the tripod legs, the nuts were very tight turning onto the bolts and a pliers, vise grips, and larger philips screwdriver were used as additional tools.

On caveat is the toe saver - a washer and nut at the end of the weight shaft which was already screwed to the shaft. It appeared to be permanently locked on so tight that nothing would remove it. As a simple solution, it was kept on, the counterweight slid onto the other end of the shaft, and the shaft was then screwed into the equatorial head. The counterweight easily removes by removing the shaft.

Remember to engage the slow motion control nuts onto the flat sides of the shafts. Setting the latitude is extremely easy. Overall the EQ-1 mount is lightweight and easy to carry. Setting it up is nearly instantaneous. I added a compass and turned the tripod and mount to calibrate to North, as the northern hemisphere is not visible from my sky window.

The second caveat is related to the red dot finder (Orion EZ Finder II Telescope Reflex Sight). The finder is held together with two side screws. This finder was assembled without any tightening of these screws. After placing it onto the OTA, it fell apart. Lucky the telescope was being moved with a plastic bag over the top and the finder fell into the bag and did not crash to the floor or break into pieces.

The final step was to install the clock drive. Printed instructions are available and are straightforward. see links

Final thoughts: the Orion StarBlast II EQ Telescope is exactly what I wanted. It's very lightweight, easy to setup and hand carries around like a small charm. The mount and tripod are already setup, just dial in your latitude and use a compass to set it facing the north pole. It works simple and might hold another small telescope set piggyback. The clock drive keeps the image in the eyepiece when polar aligned and overall the system should be good for lucky imaging. This is the telescope I can lift and move around, and will get the most use. By comparison, I'm not able to lift or move a Celestron CGX/L 14". Is there a downside to the 4.5-inch telescope? Not really - just keep in mind the lightweight mount will require a few seconds to settle down each time the telescope is moved or touched.

Orion StarBlast Webpage

https://www.telescope.com/Orion-StarBlast-II-45-Equatorial-Reflector-Telescope/p/116895.uts

Orion EZ Finder II Telescope Reflex Sight Webpage

https://www.telescope.com/Orion/Orion-EZ-Finder-II-Telescope-Reflex-Sight/rc/2160/p/7228.uts

Orion AstroTrack Drive for EQ-1 Equatorial Telescope Mount Webpage

https://www.telescope.com/Orion/Orion-AstroTrack-Drive-for-EQ-1-Equatorial-Telescope-Mount/rc/2160/p/99600.uts?keyword=astrotrack%20motor%20drive

Instruction & Assembly Manual

EN: Orion StarBlast II 4.5 Equatorial Reflector Telescope

https://www.telescope.com/assets/product_files/instructions/29576_03-17.pdf

How to Set Up the Orion StarBlast II 4.5 Equatorial Reflector Telescope - Orion Telescopes (YouTube video by Orion)

https://www.youtube.com/watch?v=BuJYoah4QU8

How to Use the Orion StarBlast II 4.5 EQ Reflector Telescope

https://www.youtube.com/watch?v=p3DbAz_QKvA

EN: Collimation of a Newtonian Reflector Telescope

https://www.telescope.com/assets/product_files/instructions/29563_11-15.pdf

EN: Orion AstrTrack DC Motor Drive for EQ-1 Mount

https://www.telescope.com/assets/product_files/instructions/29154_11-14.pdf

New Orion Telescopes on Order

New Orion Telescopes on Order
The goal is to have old school smaller telescopes which are lighter weight, easy to carry, fast to set up, adjustable, occupy a small footprint, and easy to use!

STARBLAST II EQ
First up is this Orion StarBlast II 4.5" EQ f/4 parabolic Reflector & AstroTrack Motor Drive is capable of astro imaging and has a total weight of only 20.7 pounds. The OTA is 4lbs. and the mount with tripod is only 11.9lbs. The German Equatorial counterweight adds a mere 4.8lbs. One welcomed old school feature is the clock drive. It can set a simple sidereal tracking drive rate with only one button. Power is from a simple 9-volt battery. Setting circles and a finder will facilitate star hopping to find deep sky objects without a computer. A computer however can dedicate

itself to imaging and processing images.

STARBLAST
The second telescope ordered is the tabletop "grab and go" Dobsonian version StarBlast. Remarkably, the total weight of this telescope is only 13lbs (7.7lbs lighter than the EQ). It can carry with one hand, and will be ideal for Lucky Imaging of sky objects where they are left to drift across the FOV without a drive, a camera takes thousands of short exposure images, and a video is captured and processed. This works for both telescopes.

TELESCOPES COMPARED

The OTAs appear to have a blue and green color variation and they come with different oculars - the EQ has better Sirius Plossls,  a 25.0mm and 10.0mm giving a magnification of 18x and 45x respectively. The tabletop comes with lesser quality Explorer II Kellner 17.0mm and a 6.0mm giving magnifications of 26x and 75x respectively. Another curious difference quoted in the specs concerns the primary mirrors. EQ has soda-lime plate glass and the tabletop has low thermal expansion borosilicate glass. Both versions offer the EZ Finder II finderscope. This is 1:1 and has no light gathering ability - it can be replaced with a standard lens finder or a cell phone with a sky app for starhopping.

ADVANTAGES ARE MANY

These telescopes are physically small taking up very little space - a footprint ideal for operating from a room and window in the home or a small observatory. The tabletop is extremely easy to use with only a simple altitude knob. The tabletop and the EQ can adjust weight by rotating and changing the OTA tube position to compensate for the addition of accessories.

MODIFICATIONS

For serious starhopping, the EZ Finder II finderscope will need to be replaced or supplemented. At 1:1 and no light gathering ability - it does not offer ability to show dimmer stars over that of the human eye. In a severe light polluted environment, it's likely the EZ Finder II finderscope will show no stars or only one or two of the brightest. It may have strength in quickly centering the Moon and bright planets. The addition of a cel phone finder with a sky app will create a push to goto telescope. These generally lose accuracy when moving across a large section of the sky, from East to West or North to South for example. However, observing from a room or deck, only one quadrant of the sky is viewed at a time and the cell phone finder will perform well.

EQ-1 MOUNT

This mount is compatible with other small telescopes, like the Orion 80mm refractor and rings. Having a clock drive gives it many advantages.

EMULATION & APPLICATIONS

Emulating a $3,000.00 4.5" aperture Unistellar eVscope with a $200 Orion StarBlast is one project, for imaging deep sky objects. Instead of trying to find objects using an unreliable eVscope's internal computer, the StarBlast telescopes will use manual starhopping to locate objects and a new technique called Lucky Imaging, with and without a drive. A computer will handle the camera software and processing.

8 Bright Stars Orion Area

Brightest Stars Around Orion

Source

Currently at around 4 am, the sky displays the constellation Orion and these bright stars. The Great Orion Nebula is an ideal First Light target for a new working eVscope and the eight listed vicinity stars are perfect for focus and mirror calibration. All listed stars are brighter than second magnitude.

Betelgeuse - Orion (0 to 1.6 mag)
RA 05h 55m 10.3"
Dec +07° 24′ 25.4"

Rigel - Orion (.13 mag)
RA 05h 14m 32.3"
Dec −08° 12′ 05.8"


Sirius - Canis Major (-1.46 mag) Dog Star
RA 6h 45m 9s"
Dec -16° 42′ 58"

Aldebaran - Taurus (-.75 to -.95 mag)
RA 04h 35m 55.24"
Dec +16° 30′ 33.5"



Capella - Auriga (.08 mag)
RA 05h 16m 41.4"
Dec +45° 59′ 52.8"



Castor - Gemini (1.58 mag)
RA 07h 34m 35.9"
Dec +31° 53′ 17.8"

Pollux - Gemini (1.14 mag)
RA 07h 45m 18.9"
Dec +28° 01′ 34.3"



Procyon - Canis Minor (.34 mag)
RA 07h 39m 18.1"
Dec +05° 13′ 29.9"

Based on the maps, the following vicinity objects are available

Map 1

NGC 2238

M78

M43

M42

Map 2

M35

M36

M37

M78

M1

Map 3

M35

M36

M37

NGC 2238

Orion Starblast

4.5" StarBlast telescope Mosaic by DaemonGPF

The Next Telescope
Orion StarBlast

I've become quite enamored with tabletop telescopes. Plus, it's astro on the cheap without computers, electronics and high tech gear that can fail.

They are lightweight, low cost, easily carried, and setup in seconds. They are self auto balancing and grab and go stature. The newer ones now have higher quality optics and they're ideal for many astronomical projects. No fussing with a computer or overly complicated electronics and star calibrations. After the recent runin of problems with computerized telescopes, my aperture fever has taken a sharp turn towards the small and uncomplicated. In upgrading from the Celestron FirstScope, the Orion StarBlast is a likely candidate. It supersizes the minuscule 3-inch mirror to one that just exceeds 4.5-inches or up to 6-inches. The biggest problem with these telescopes, they are all sold out and unavailable at this time. Here's a rundown of total telescope weight for tabletop small telescopes.

  

$54.95    Celestron FirstScope 3" Dob    - 4.3 lbs
$199.99   Orion Starblast      4.5" Dob  - 13 lbs
$349.99   Orion Starblast      6" Dob    - 25 lbs

Photo
The Ring Nebula M57 imaged through the Orion StarBlast 4.5" F4 telescope with tracking. Source CC by 2.0. The next image of Orion is with the StarBlast 4.5" and the NightCap app on a smartphone. Starblast photo by Mike Otis.

Nightcap
Many people are using the NightCap camera app. For $3 you can have a complete astro camera on your smartphone, capable of taking time exposures, video in low light, and capturing deep sky objects on a shoestring budget - matching low cost small tabletop telescopes.

https://nightcapcamera.com/

Review
https://allthestuff.com/orion-starblast/

https://astronomy.com/-/media/import/files/pdf/9/d/d/0104_orion_starblast.pdf

Image Gallery
http://tidalsoundings.blogspot.com/2016/04/adventure-in-astrophotography-begins.html