CCD suitability & possible changes

[Andy274]

Hi guys, 

I've 2 scopes - a 70mm triplet apo & a 110mm apo from altair. I have the zwo 533 on the triplet & an atik 383L + mono on the 110mm.

After finding the suitability scale, it seems that my atik 383L is way off with my triplet giving significant under - sampling & I wouldn't mind doing some mono through the 70mm & putting the 533 on the 110mm

Would you guys recommend I chop in my atik & get a better matched camera for my setup or am I way over-thinking this?

Confused

Cheers

Andy

[pete_l]

21 minutes ago, Andy274 said:

After finding the suitability scale, it seems that my atik 383L is way off with my triplet giving significant under - sampling

This scale?

The numbers look fine to me. Personally, I'd say that there is a huge "acceptable" arcsec/pixel  range for most situations. You can get great photos anywhere from <0.5 arcsec to 5+ arcsec. Just look on Astrobin and you will see all sorts of numbers and some excellent end results.
Since you already have the equipment, the ultimate test is to set it up and try it out.

[Andy274]

Yes that scale & I know its fine on the 110mm - it's the 70mm I want to use a mono camera on

[Laurin Dave]

I’d just put your 383 on your 70mm frac (what focal length) and see what you get.. pretty sure it’ll be ok in terms of resolution (I’d guess 3”/pp or finer which is perfectly fine, there are great images out there from Tak106/kaf11000 chip at 3”/pp) and  it will have a good fov for larger objects..  and with narrowband you’ll get small stars..  the alternative camera with the same chip size but smaller pixels is the ASI1600 but that’ll only increase resolution to 2.25”/pp which when looking at full frame on a screen won’t  be unnoticeable..  and on bright suffers  (depending on the scope) from microlensing artefacts around bright stars..  the ASI183 or equivalent will give 1.5”/pp but it has a smaller chip and the fov will Id guess be little larger than that with your 383 on the 110 scope..  

hth

Dave

[Andy274]

56 minutes ago, Laurin Dave said:

I’d just put your 383 on your 70mm frac (what focal length) and see what you get.. pretty sure it’ll be ok in terms of resolution (I’d guess 3”/pp or finer which is perfectly fine, there are great images out there from Tak106/kaf11000 chip at 3”/pp) and  it will have a good fov for larger objects..  and with narrowband you’ll get small stars..  the alternative camera with the same chip size but smaller pixels is the ASI1600 but that’ll only increase resolution to 2.25”/pp which when looking at full frame on a screen won’t  be unnoticeable..  and on bright suffers  (depending on the scope) from microlensing artefacts around bright stars..  the ASI183 or equivalent will give 1.5”/pp but it has a smaller chip and the fov will Id guess be little larger than that with your 383 on the 110 scope..  

hth

Dave

I had a 72mm WO doublet that I got some great shots  on using that 383L. Its just being presented with new information that put me into a flat spin. 

Was ready to sell it & get a 183 instead... 

The FL of the Altair triplet is 432mm (I think) 

Thanks for all your input - it's saved me from a grave mistake as I love that camera

Andy

Edited January 26, 2020 by Andy274

[Laurin Dave]

22 minutes ago, Andy274 said:

I had a 72mm WO doublet that I got some great shots  on using that 383L. Its just being presented with new information that put me into a flat spin. 

Was ready to sell it & get a 183 instead... 

The FL of the Altair triplet is 432mm (I think) 

Thanks for all your input - it's saved me from a grave mistake as I love that camera

Andy

Good..  the 383 is a great camera..     just re read my initial post and notice a typo..   meant to say that the difference in resolution on wide field would be unnoticeable!  Looking forward to seeing some results 

Dave

[newbie alert]

A few years ago I drove myself nearly to insanity with sampling rates.. but as it was really mount and focuser sag that I was seeing, once that was rectified there was never a issue with undersampling..at the time I was sampling at 3 arc sec per pixel, I've seen plenty of amazing images at 3.5 pp and have never seen these blocky stars they talk about..if you're blowing the images up to poster size then maybe it could happen but not on a pc or phone..