Connect Sony Cybershot DSC-H20

cloud_cover · Post by **cloud_cover** » Sun Jan 23, 2011 11:33 pm

Not sure if that's a kidney beaning defect (a blackout spot on the eyepiece if positioned inappropriately) or the shadow of the secondary.
You'll need advice from the more experienced guys.
However, from my understanding unless you're using a particularly long focal length EP the secondary should not be visible.

kensou · Post by **kensou** » Mon Jan 24, 2011 12:26 am

I need not just t-ring.. ill need eyepiece with threads >.<

Post by **weixing** » Mon Jan 24, 2011 8:29 am

Hi,
Hmm... May be you can check with Mr Chia (superiorstream) on this... he is using afocal, so he might be able to give more practical advice and other method of connecting your camera to the eyepiece.

Happy imaging and have a nice day.

kensou · Post by **kensou** » Mon Jan 24, 2011 10:07 am

After some thoughts I think it is better for me to use camera mount.. cheaper lol..

I have another question.. if I use 6mm EP den how to use afocal? lol the hole so small.. any tips?

superiorstream · Post by **superiorstream** » Mon Jan 24, 2011 10:56 am

Hi,Kensou
Your method is basically afocal method of photoography.
1)From the photo I saw,I think you are using a reflector and a long focal length eyepiece--greater than 25mm.;eg 32 or 40mm.Under such circumstances,the centre dark hole--due to the second mirror in the reflector will DEFINITELY show up.When using high power ep,its always there.Actually this make shotting of say star cluster very difficult using afocal method with reflector.Basically use it for planet and moon close up.For cluster,use a refractor and a well corrected f/5 ,120mm with a 15-17mm eyepiece giving a field of aprox 1.5 degree and that can net in many star cluster available in our light polluted sky ,including the pincushion cluster.
2)As for connecting ep to camera;there is no fix method or universal solution.Most of the new generation of compact camera have no thread in the front of the lens or in front of the lens.Hence,ingenious method has to be self invented to overcome it;----eg,macgill 'universal adapter dont suit your camera due to your camera lens size.However Orion has one that might work---and now on offer too.If you are keen,see no 4.
3)Most ep has no thread for mounting camera--except hyperion--andso some ingenious method need to be found.That Orion mount did work,but personally I always fear it might compress the ep too much and break the lens of the ep.
4)Orion SteadyPix Deluxe Camera Mount #05338 is the mount I am talking about and if I am not mistaken;Joo Beng is selling it.
My 2 cents.Thanks.

kensou · Post by **kensou** » Mon Jan 24, 2011 11:07 am

I am using Orion Starblast 4.5, when I took the photo, I was using Meade Plossl 20mm EP. So are you trying to say no matter what I cant do star cluster photography?

I feel like using the orion Steadypix camera mount but the problem is when i point my camera to the eyepiece i can see the blackdot which makes me have a 2nd thought should I buy.

My camera has adapter ring that have inner screwthread of 58mm.. which can work with hyperion 58mm t ring but I heard I'll need eyepiece wif screwthreads

As for the long focal thing how do I overcome this problem? I also have a 6mm EP.. I dun think my camera can zoom into that small hole eh?

superiorstream · Post by **superiorstream** » Mon Jan 24, 2011 11:13 am

Hi,Kensou
Just read your pm;I think must tell you one more thing--afocal photography method also has a big problem--vignetting--and ITS EYEPIECE DEPENDENT--hence a particular ep that work for scope A might not work with scope B.
Also there is the issue of lens matching.;eg a ep with a say 1cm diameter lens on the eye side cannot take a camera with a say 2cm diameter lens.If you fix them together severe vignetting result.In short the rule of thumb is--lens of camera should be smaller or equal lens diameter of eyepiece.
In short,its a very trial and error procedure and the only good point is that you can use the magnification and the correction--colour,coma-- offered by the eyepiece to your photographic needs.

kensou · Post by **kensou** » Mon Jan 24, 2011 11:19 am

i think the smallest I can use with is would be 20mm EP.. if not like u say vignetting occurs.. but I can still do it with barlow to magnify.. but the problem of long focal still exist I suppose

1 more thing is.. who is Joo Beng? and how much is he selling for? I would like to buy..

superiorstream · Post by **superiorstream** » Mon Jan 24, 2011 11:20 am

Hi,Kensou
Yes,for long focal length ep,no solution--perhaps you can use DSLR--ask the expert.Afocal wise I have no solution for wide field using reflector.
Another connection method is the sborg sd-1x,but its expensive with the skyhigh yen.

superiorstream · Post by **superiorstream** » Mon Jan 24, 2011 11:25 am

Hi,Kensou
Joo Beng is astrobargain.Other singastromember can help you get the link;I dont know how to do it.If 20mm ok,then with the bracket you can shot already.Thanks.