SCB-2000 with C8 at F6.3

[Astro_king]

Hi,

I tried to connect the SCB-2000 with my C8 for some live views but I was left very disappointed as the zoom on stars was tooo much even at F6.3.

 

I couldn't even find objects slewed onto after I had focused the scope on Vega.

 

Attached is a picture of Caph at 8 second exposure for reference.

I had the C8 mounted on heq5. I plan to install a fast refractor on top of the C8 for DSLR photography so wondering if the SCB-2000 is best suited for wide field refractors? If yes which ones are the best to use?

Thanks

[DAVE AMENDALL]

There is quite a bit of info on Cloudy Nights Astro Forum on the SCB-2000 and also the earlier Samsung models.You would think that F6.6 would have yielded better results................Dave

[RobertI]

The SBC2000 appears to have a tiny chip (even smaller than the Lodestar camera which I use) so even at F6.3 it covers a very small area of sky. Using an F3.3 reducer would almost double the field of view and this kind of reducer was designed specifically for tiny chipped webcams like this so should work well. May be worth tracking one down as the SBCs have a good reputation for EAA/video I believe and should produce nice results with the F3.3 reducer. The SCB + C8 + F3.3 reducer combination has been widely used in EAA/ video for many years so should work but you will of course get a much wider field of view with a small short FL refractor + reducer, so choose the scope to fit the target. Good luck!

[Astro_king]

20 minutes ago, RobertI said:

The SBC2000 appears to have a tiny chip (even smaller than the Lodestar camera which I use) so even at F6.3 it covers a very small area of sky. Using an F3.3 reducer would almost double the field of view and this kind of reducer was designed specifically for tiny chipped webcams like this so should work well. May be worth tracking one down as the SBCs have a good reputation for EAA/video I believe and should produce nice results with the F3.3 reducer. The SCB + C8 + F3.3 reducer combination has been widely used in EAA/ video for many years so should work but you will of course get a much wider field of view with a small short FL refractor + reducer, so choose the scope to fit the target. Good luck!

Thanks.

I have in the past managed to see andromeda galaxy and one cluster from the double cluster and possibly blue snowball nebula although I couldn't believe I was seeing the nebula through immense light pollution near city centre Manchester but I checked later on and it indeed was the blue snowball nebula so the camera is nothing short of amazing and I saw all this through a F10 Nexstar 5se so was quite surprised that the field of view was still quite small on f6.3.

 

will try the 3.3 if it's decent priced.

 

[RobertI]

2 hours ago, Astro_king said:

will try the 3.3 if it's decent priced.

Unfortunately Meade don't make theirs anymore but they do come up used for around £50 -£70 ish. You could always try a wanted ad.

[Astro_king]

17 hours ago, RobertI said:

Unfortunately Meade don't make theirs anymore but they do come up used for around £50 -£70 ish. You could always try a wanted ad.

I just did some research regarding the 3.3 reducer and had a light bulb moment. My friend at work gave me a focal reducer for a fiver which attaches to your eyepiece and was supposed to give wider views. I can honestly say it was the most useless reducer ever it would make the image slightly wider but reduce the field of view immensely.

 

From my flat, I had used this focal reducer on top of the SCB and tested it out and had managed to see objects fine. At least they would come in view easily.

 

Having read about the 3.3, this is what people are saying, it reduces the FOV dramatically so that webcams with small chips can focus and show a wider field.

I suspect the wide field of view on the 6.3 was the problem.

I am going to try and use that focal reducer on top of the 6.3 FC and see what I get. 

It doesn't say what it is i.e. 3.3 or else but worth a try next time.

 

[shirva]

The Samsung scb 2000 is a 1/3 rs sensor and imitates the view that you would get from a 6mm eyepiece or there about,, I usually used a flip mirror with my Sammy made life a lot easier

[RobertI]

6 hours ago, Astro_king said:

It doesn't say what it is i.e. 3.3 or else but worth a try next time.

 

Let us know how it goes. Looks like you have a nice comfortable viewing set up there! 

[JamesF]

5 hours ago, shirva said:

The Samsung scb 2000 is a 1/3 rs sensor and imitates the view that you would get from a 6mm eyepiece or there about,, I usually used a flip mirror with my Sammy made life a lot easier

Is that the field of view of a 40 degree 6mm BGO, or an 82 degree ES 6.7mm, or a 100 degree 6mm Ethos?

James

[Astro_king]

50 minutes ago, RobertI said:

Let us know how it goes. Looks like you have a nice comfortable viewing set up there! 

This was 4 years ago. I made tea and had it with andromeda galaxy live ?

Now I have moved into a house and intend to achieve this on my C8 which will be setup in an observatory with connection to living room Tele again tea with some awesome DSOs if this hack works - hopefully.

[shirva]

1 hour ago, JamesF said:

Is that the field of view of a 40 degree 6mm BGO, or an 82 degree ES 6.7mm, or a 100 degree 6mm Ethos?

James

Standard plossil, I don't use eye pieces 99% of the time,, just use live view from camera's, stopped using my Samsung about a year ago or so when I went on to DSLRs and backyard Eos

[shirva]

My heavily modified Samsung scb2000 with flip mirror and 6mm eyepiece

[JamesF]

49 minutes ago, shirva said:

Standard plossil, I don't use eye pieces 99% of the time,, just use live view from camera's, stopped using my Samsung about a year ago or so when I went on to DSLRs and backyard Eos

Even plossl eyepieces have varying fields of view and different field stop sizes though.

My point is that the whole "same field of view as a 6mm eyepiece" thing can be a misleading description because "your eyepiece may vary", be it a plossl or otherwise.  Also of course the FOV of the camera is rectangular and that of the eyepiece is circular.

If you do the maths for a 52 degree eyepiece (which is one of the common fields of view for a plossl, I believe), then the field of view across the width of a 1/3rd sensor is about the same as you'd get with an eyepiece focal length of a smidge over 5mm.  The field of view across the height of the sensor is about what you'd get with a 3.5mm eyepiece.  The field of view across the diagonal is closer to the 6mm eyepiece, so perhaps there's a sense in which the comparison might be valid there.  However, the actual area of the sky that you'll be able to see in a 6mm 52 degree eyepiece is about 70% greater (assuming I've done the calculation correctly than with the 1/3rd sensor in the same telescope.

So my assertion is that it's a messy and confusing comparison.  And not only that;  it can tempt people into believing that cameras behave in other ways that are similar to eyepieces, such as having magnification.  And then you have a whole catering size can of worms spilt on the floor

James

[RobertI]

6 hours ago, shirva said:

Standard plossil, I don't use eye pieces 99% of the time,, just use live view from camera's, stopped using my Samsung about a year ago or so when I went on to DSLRs and backyard Eos

Interesting development Shirva, sounds like you have been getting on well with the Canon for live viewing. I dabbled with imaging using my Canon 1100D + 72mm frac + 0.8 reducer + BYEOS - do you think this would work for live viewing? Did you manage to post any results on SGL (sorry if I missed it)?

Sorry to OP for derailing thread btw. 

[shirva]

11 hours ago, JamesF said:

Even plossl eyepieces have varying fields of view and different field stop sizes though.

My point is that the whole "same field of view as a 6mm eyepiece" thing can be a misleading description because "your eyepiece may vary", be it a plossl or otherwise.  Also of course the FOV of the camera is rectangular and that of the eyepiece is circular.

If you do the maths for a 52 degree eyepiece (which is one of the common fields of view for a plossl, I believe), then the field of view across the width of a 1/3rd sensor is about the same as you'd get with an eyepiece focal length of a smidge over 5mm.  The field of view across the height of the sensor is about what you'd get with a 3.5mm eyepiece.  The field of view across the diagonal is closer to the 6mm eyepiece, so perhaps there's a sense in which the comparison might be valid there.  However, the actual area of the sky that you'll be able to see in a 6mm 52 degree eyepiece is about 70% greater (assuming I've done the calculation correctly than with the 1/3rd sensor in the same telescope.

So my assertion is that it's a messy and confusing comparison.  And not only that;  it can tempt people into believing that cameras behave in other ways that are similar to eyepieces, such as having magnification.  And then you have a whole catering size can of worms spilt on the floor

James

Sorry James Im more the stick it in and try it brigade,, I haven't got involved in the maths of eyepieces ect,, each to there own,, the eyepieces I have I got came with a second hand scope I got years ago,, I just used it in the flip mirror to help getting the focus in the Sammy , I found I had problems finding the focus point for my Samsung when I first put it on a sw st102,, once I marked the position I didn't really need it much after that,, 

I was just pointing out that a flip mirror can be a useful bit of kit

[shirva]

5 hours ago, RobertI said:

Interesting development Shirva, sounds like you have been getting on well with the Canon for live viewing. I dabbled with imaging using my Canon 1100D + 72mm frac + 0.8 reducer + BYEOS - do you think this would work for live viewing? Did you manage to post any results on SGL (sorry if I missed it)?

Sorry to OP for derailing thread btw. 

As Robert said sorry for going off subject, but will answer his question.

I use sw ed80, with the sw 0.85 focal reducer and have a unmodified canon 600d and 400d modded, I use byeos and astrotoaster together,,it works for my needs,, if you search utube a friend has put up tutorials on astrotoaster , he uses canon utilities and astrotoaster,, same principles,, we are both waiting on sharpcap adding DSLRs to its list of camera's it supports,,

 

[shirva]

I see you are linked directly to your TV,, using a usb video grabber and sharpcap would give you more control than viewing straight to the TV.

Another useful piece of kit is a UTC... Up the  coaxial controller,,  allows you to control the camera menu away from the camera.

[stash_old]

7 hours ago, shirva said:

Sorry James Im more the stick it in and try it brigade,, I haven't got involved in the maths of eyepieces ect,, each to there own,, the eyepieces I have I got came with a second hand scope I got years ago,, I just used it in the flip mirror to help getting the focus in the Sammy , I found I had problems finding the focus point for my Samsung when I first put it on a sw st102,, once I marked the position I didn't really need it much after that,, 

I was just pointing out that a flip mirror can be a useful bit of kit

Nothing wrong with "try it Brigade" - Maths is NOT the answer to all our prayers - e.g. does nowt for cloudy nights 

[stash_old]

21 hours ago, shirva said:

As Robert said sorry for going off subject, but will answer his question.

I use sw ed80, with the sw 0.85 focal reducer and have a unmodified canon 600d and 400d modded, I use byeos and astrotoaster together,,it works for my needs,, if you search utube a friend has put up tutorials on astrotoaster , he uses canon utilities and astrotoaster,, same principles,, we are both waiting on sharpcap adding DSLRs to its list of camera's it supports,,

 

Astrotoaster also works with AP. So you have a list to choose from. - You may  have a long wait for Sharpcap adding DSLR's - nearly as long as me waiting for APT to do PA as per Sharpcap.

[JamesF]

2 hours ago, stash_old said:

Maths is NOT the answer to all our prayers - e.g. does nowt for cloudy nights 

You can still do maths on cloudy nights

James

[stash_old]

11 hours ago, JamesF said:

You can still do maths on cloudy nights

James

You should have plenty of time then 

[JamesF]

Far more than I'd like, believe me   And that's even after spending three or four evenings a week coaching swimmers.

James

[shirva]

I see you are linked directly to your TV,, using a usb video grabber and sharpcap would give you more control than viewing straight to the TV.

Another useful piece of kit is a UTC... Up the  coaxial controller,,  allows you to control the camera menu away from the camera.

[Astro_king]

On 13/09/2017 at 15:29, shirva said:

I see you are linked directly to your TV,, using a usb video grabber and sharpcap would give you more control than viewing straight to the TV.

Another useful piece of kit is a UTC... Up the  coaxial controller,,  allows you to control the camera menu away from the camera.

I was actually wondering in how to send the feed to the laptop instead and then remotely look at the laptop screen using RDP.

But one step at a time.

first going to try that small used focal reducer and see if it works...

[shirva]

Never used my Samsung with a focal reducer,, I did get a 0.5 one off of eBay ( joy) never got much luck with it,, 

Try it brigade again,,lol

But when I got my sw ed80 I did get the Skywatcher matched 0.85 one and it makes a nice difference.