NGC253 with an 80ED and Meade DSI

[[1ponders] (Paul)]

It aint no Narayan shot but for a first night out and first DSO using the DSI with pretty much default settings I'm quite surprised. About 2 minutes of tweeking with levels and curves and switched to greyscale (looked better ) and compressing it for uploading. I'm looking foreward to doing a side by side comparison with the 300D and taking my time with the processing. Should be an interesting exercise.

[atalas]

Its a good effort Paul with a DSI , I'm doing an hour of exposures myself on this one tonight . I'm hoping I get a better result than my first effort of a 30min exposure .

Louie

[gbeal]

Nice Paul
One thing I do see though is the stars are more "blobby". I have always put this down to the smaller chip giving a bigger image scale, is this correct??
Still a cracker though. You will need to list this on the Robbie real estate list as well.

Great first attempt with a new camera Paul,

There is a yahoo group called Meade_DSI that can answer any questions,
including Gary's Q about bloated stars, which has something to do with the
pixel wells size in the chip. I'm not fully sure of all the techical details.
There's also a bloke in Oz who has designed a cooling system for them too,
which I thought I saw being sold through Bintel, you'll be paying $300.00+ for
that extra.

regards,CS

[davidpretorius]

yay paul,

i will have your 300d, now that you have upgraded to the dsi,

thanks mate!

[iceman (Mike)]

Nice shot paul, interested to see how far you can push the DSI and also the comparison with the 300D.

I'd guess the 300D will come out on top 9 times out of 10, but maybe i'll be wrong.

[[1ponders] (Paul)]

Thanks everyone. Imaging isn't the main reason I bought the DSI but I am interested in how it performs.

Louie, this shot is a total of 35 images at 30sec exposure with autodarks. It was quite dim on screen but pulled up quite bright with some PS tweeking.

Gary and Rob. I don't know about the "blobbiness", though I was aware of the issue when I bought it. The pixel size is 9.6X7.5 if I remember correctly. Compared to the ToUcams 5.6X5.6 and the LPI's 8X8. Rob I'm already thinking of ways to cool it. It should be easy enough to build a jacket for it and drop some dry ice into it

Thanks for the offer Davo but I'll see if I can modify the 300D to autoguide for the DSI

Mike I think the DSLR would win 10 times out of ten for resolution, but the DSI would win for colour range. I'm hoping to do a comparison over the next few weeks. I'll let you know how it goes

[Striker (Tony)]

Great start with the DSI Paul.....

I am intersted in your thoughts regarding guiding comparing to the toucam...any thoughts so far Paul.

I can not pick up anything mildly dim with the toucam to guide on....I expect the DSI is much better.

[[1ponders] (Paul)]

What exposure, frame rate and gain settings are you using Tony?

[Striker (Tony)]

From memory 1/25 no gain high brightness and 10fps....

[ving (David)]

I like that image!
good one!

[[1ponders] (Paul)]

Try 1/25, 60-75% gain and 5 fps. I find a lot more stars if I use settings in that rang. First off though I find a relatively bright star somewhere close and make sure your focus is spot on. For the bright star I use a low gain and drop the brightness until the image is only fairly small and not too bright. Then whack on a hartmann mask to achieve final close focus. Once I've done that I then swing back to the area I want to image and use the first settings I mentioned. Don't forget to take the hartmann mask off.

As a side note, if you have a bright star to guide on, leave the hartmann mask on. I've found that it helps reduce the effect of poor seeing when trying to guide so the star doesn't tend to jump all over the place and "flare" everywhere. In fact make a hartman mask with 20 or so 6mm holes in it. I found it made quite a difference in guiding stability. Don't use it for focusing just for guiding.

[Striker (Tony)]

Thanks Paul.....will give it a go.