Is ASI187MM worth buying for a 6" newt?

[jakicevichap]

Hey guys! I'm not sure what to do. I currently have a t7c astro camera (asi120mc clone) and would like to get a better planetary camera. I'm eyeballing the ASI178MM as I've seen some amazing work done with it, but can't find anything substantial on using it with a 6" scope. My scope is a Skywatcher Explorer 150p and I usually use a 3x barlow as well as a svbony ir-pass (685nm) filter when doing high res lunar mosaics. I've seen some awesome work with 127mm scopes and the asi178mm which is why I can't wrap my head around what the results might look like. Will using an asi178mm give me a better result than the t7c when used on same focal lengths (2x, 3x barlows)? I understand that the resolution might be similar between "asi178mm + 2x" and "t7c + 3x" which could help me save time when doing huge mosaics, but is that all that I'd gain from this (not much better resolution?)?

Let me know please as I'm in a bit of a conundrum. Thanks!

 

You can find my work with the t7c here.

[vlaiv]

Hi and welcome to SGL.

If you properly use both cameras - you won't see great improvement.

ASI178mm is excellent camera - but ASI120 (and clones) - are fairly potent cameras as well.

I would rather concentrate on getting the most out of your current camera - and only if you are not satisfied of how it works for some reason - then change it.

Sharpness of the image has very little to do with camera used. It has more to do with the way you capture and process your images - and that is not likely to change when you change camera.

One thing to be careful about is diffraction limited field of Newtonian scope. Your scope is F/5 newtonian. It is quite fast scope. It has very small diffraction limited field - around 2-3mm in diameter. If you use x2 barlow (and at 685nm - optimum sampling rate for 3.75µm pixel size is F/11 - so it's better to use x2 barlow) - that is only around 5mm in diameter.

If you get camera with diagonal larger than that - coma will start to affect the corners. Btw - at 2.4µm and 685nm - optimum sampling rate requires even faster scope - F/7 scope - so its almost not worth using barlow at all.

Maybe best course of action would be to get 150PL Newtonian - F/8 version. That will be much better scope for Lunar imaging.

[jakicevichap]

Alright, thanks for the input! I'm leaning towards getting it since my t7c sucks to be frank. It lived a good life, but never trust a clone to recover well from 60s subs... 💀😂

Hvala ti još jednom!

[vlaiv]

1 hour ago, jakicevichap said:

Alright, thanks for the input! I'm leaning towards getting it since my t7c sucks to be frank. It lived a good life, but never trust a clone to recover well from 60s subs... 💀😂

Hvala ti još jednom!

In that case - go for it.

I have ASI178mcc (color cooled version) and it is quite nice camera to work with.

Here is lunar mosaic that I did with that camera (102mm Sky Watcher Maksutov)

http://serve.trimacka.net/astro/Forum/2020-07-30/moon.png

(right click / open in new tab)

 

[Nigella Bryant]

I've two 178mm for solar work which are great. I've used a 224mc for planets which is good too, old now but good. The 178mm on my 60mm Lunt solar scope and 80mm white light scope but the 224mc on my C11. Challenge is more to do with seeing and lucky imaging I think. 

[Ags]

I use the 178MM with a C6.

[Paul M]

Another vote for the ASI178. I find it to be very sensitive. This was taken through my 10" Newt but in more skilled hands it would be better than this

Two downsides in my experience. Amp glow is a nuisance and dark frame calibration is essential, it's also a small sensor with small pixels. This image is uncropped. 

I've now expanded my family to include an ASI071 to address the above issues but, both cameras are great.

[neil phillips]

Another 178m fan. Boy does it help  lunar mosaic work. Over smaller sensors

Edited November 8, 2021 by neil phillips