The Moon with a 76mm

[Thefatkitty]

Hi again all,

Yesterday was almost productive for me. Got off work early (always good) and got home to sunshine and a new spot from the up and coming Solar Cycle 25. Come on, Solar Cycle 25!! People like me are waiting...

After I hoovered up some dinner, I went back out with a cold beer. After 9PM the sky started to darken, and I could see the setting 13.5% waxing crescent Moon heading toward the horizon. Hmmm... Well, I'm sitting here waiting for NEOWISE. Should I have another beer or be productive? Hey wait, let's multitask and do both!

A while ago, when it was cloudy and lockdown was in effect, I merged two scopes into one with some mods. Let me explain, hopefully in 500 words or less

About 6 years ago now, my daughter and I were at a garage sale. Amongst the other items, there was a Tasco 55VTE, a Safari 60mm at f/15, and a 76mm Skywatcher newt. No mounts, just the scopes. I could see the primary on the SW was oxidized, but oh well. The people having the sale were happy to let all three go for the princely sum of ten dollars. Sold.

So, the Tasco 55VTE objective was used to make my Towatron. Love this scope. The Safari I haven't done a thing with. The Skywatcher.... Well, about a year or so ago, I picked up two 76mm's within two weeks of each other. One is a Towa on a nice wooden alt-az mount. The other was a Tasco 3TE, which is nothing more than a re-branded Towa. Scope was great, mount, well, no.

That led me to try an experiment. I took the primary mirror and cell, as well as the secondary from the Tasco 3TE. Next, center circled the primary, and mounted it all in the Skywatcher tube. Yup, works fine. I then took out the focuser and used my DSLR in its place. Found focus with all that on the Moon and made some measurements; ie how far away is the camera's T-ring from the tube compared to the lowest point it sits on the focuser. Using that measurement, I cut the appropriate length off the back of the SkyWatcher tube. Funny thing is, it was exactly 76mm's....

I fabricated a tube-ring for it so I could mount the scope on my CG4. When assembled, the whole mess looks like this (the red "light" is actually the reflector on my bicycle):

By now it was 9:30 and the Moon was sinking lower. I took 20 frames with my T2i at ISO 800 and 1/100th sec exposure. For what the scope is, I was happy with the result. Some mild processing in Registax:

For comparison, this was done a few minutes after with my C80-HD, an 80mm achro at f/11.4. Same camera and ISO, just at 1/320th sec exposure. Took 20 frames, and same processing settings in Registax as with the 76mm:

I have to admit, I think the one done with the C80-HD is a little sharper, though the 76mm gives no false "cheesy" achro coloring.

Tonight is supposed to be clear. I have an appointment this afternoon, I'll see how that goes and how the weather holds. Running out of time to see NEOWISE here.

Have a great day/night all!

[Lady Fraktor]

It seems you have another setup that will work well for you.
I hope you get lots of use from it

[Greenman]

Nice work all round, on the engineering, front and the images, I prefer the reflector image without CA.

[Gordon]

Congratulations Mark on having your image selected as todays TSS APOD!!!

app.php/article/7-24-2020-tss-astrophot ... of-the-day

[Makuser]

Hi Mark. You grabbed a couple of great waxing Crescent Moon images of the Mare Crisium region with both telescopes, and I can make out Crater Picard in both. Thanks for sharing these captures with us Mark, and congratulations on winning the TSS APOD Award today.

[TheButcher]

Very Nice Mark and Congrats on the APOD!

[helicon]

Looks great Mark and congrats on winning the APOD award for today!

[Ruud]

Great job, Mark, and kudos for the APOD!

[Thefatkitty]

Wow, thanks for the comments all! And thanks Gordon, though to be honest, I wasn't even going to bother as I didn't think much of them... Although I was pleased with the reflector for sure
The only reason I made the post is because I was waiting to go to a doctor's appointment; they called me yesterday to go in. I'll spare you the details, but the news was either going to be really bad or good. So making this post was my way of coping with the stress of that...
Thankfully all is good so far, and reading all the comments and the APOD really was nice icing on the cake. Thanks everyone!

All the best,

[Juno16]

Really nice report Mark. Your lunar images are fabulous! Congratulations on the apod!!!

I sure hope that tonight is a good one!

Rain here all day from a tropical storm in the Gulf of Mexico. Another heading into the gulf and a disturbance moving this way off the coast of Africa. Rough time here!

Looking forward to a good report Mark!

[Bigzmey]

Nice shootout Mark! Don't tell Gabby, but I also prefer the reflector image.

[notFritzArgelander]

Hope your news is good and thanks for the images.

I understand your concerns about color but the image with the refractor is more detailed and contrasty.

[BABOafrica]

Hard to choose which one I like better. Anyway, very nice and Congrats on the APOD!

BABO