compact digital beats DSLR

[Ramjo]

Hi all

I've been messing around with astro photos for a couple of months now, mainly the moon, planets and orion

Started off using my wife's sony 8meg compact against the eyepiece with a modified orion mount using the camera's timer, getting good results, espicially the moon

so with the arrival of my Nikon d5000 12meg dslr i was expecting a vast improvement, using 2 stacked 2x 2" barlows and a t adaptor

Truth is the results aren't as good i'm not getting as much sharpness with the moon and Saturn has false colours around it

I'm using live view to focus, a rmote shutter release and my polar aligment is spot on, only thing might be i'm using a cheap barlow with a powermate untill my 4x powermate arrives

I can't believe a cheap digital could out perform a dslr any suggestions??

[Shibby]

Ramjo, the barlows are the cause of the fringing and probably also of the poor sharpness. Assuming the pixel sizes are comparable on the two cameras, you should try imaging without the barlows if you want to compare the two.

Also, the focus is critical with your DSLR - without its own lens and AF, you will ideally need to use a focusing mask such as the Bahtinov to achieve a good focus.

The DSLR will really come into its own on DSOs, particularly if/when you start taking longer exposures and stacking them.

[RikM]

For the moon and planets a cheapo webcam will thrash a DSLR as you can take many hundreds of short exposures (as an avi file) and compile them into a single final image using Registax.

Long exposures for deep sky objects are where your DSLR will come in.

[Tinker1947]

Download DeepSkyStacker (its free) and read the help files, get a T-Ring/Adapter to suit your camera and set it up in "Prime Focus Mode" and a remote camera timer like the one listed...

http://www.astronomyforbeginners.com/astrophotography/prime-focus.php

DeepSkyStacker - Free

http://www.p-buy.com/index.php?route=product/product&product_id=10302&currency=GBP

[Mr TamiyaCowboy]

compacts are ok and do well , but they also convert to a jpg or other format. ok to shove on a website. but anything more all the data was lost when it was converted.

your Dslr captures raw data and gives you a raw format picture file. this is all the data collected, the good bad and ugly, unlike above. more raw data is better to play with and the dlsr tends to have a lot larger imaging sensor.

i think a DSO capture will let you see what your Dslr can really do better than a compact.

[GJBC]

Use the DSLR, Loose the barlow and if you have to crop the image do so. all the right info has been said above and i agree with all. Focus is key and that is what you have to work on.

I always used to focus on a nearby double star i.e. Albiero, Alcor, Mizar or in your case i used to use the trapezium in Orion the nebular. i never used single stars that was just the way i done it it always seemed to prove better. once i was happy withe the focus i would then move to the object for imaging. i always used deepskystacker for deep sky objects and images off the DSLR.

i never used a DSLR for planets though to much like hard work, i always used a web cam and registax.

hope it helps

[RikM]

compacts are ok and do well , but they also convert to a jpg or other format. ok to shove on a website. but anything more all the data was lost when it was converted.

your Dslr captures raw data and gives you a raw format picture file. this is all the data collected, the good bad and ugly, unlike above. more raw data is better to play with and the dlsr tends to have a lot larger imaging sensor.

i think a DSO capture will let you see what your Dslr can really do better than a compact.

Yes...but it's a Nikon so not proper RAW...(runs and hides )

[Stephen]

Yes...but it's a Nikon so not proper RAW...(runs and hides )

Oh meeow! LOL

[Ramjo]

Yes...but it's a Nikon so not proper Raw

oh well I bet it's plenty enough for my humble needs,

It has a HD movie function would this not be better than a webcam for collecting data to use with Registax?

[RikM]

Only joking The low noise will get you lovely long exposure images.

You can try the movie mode for sure but it is normally just that the size of the planet compared to the size of the chip means it gets a bit lost. I tried exporting the liveview feed from my Canon 1000D and it was pretty hopeless. A Philips webcam or a QHY5v do a much better job so that's what I use instead but lunar / planetary imaging is not really my bag.

[dph1nm]

Compacts are much maligned on this forum (and others). In fact, some have lower read noise than DSLRs (they have to have for terrestrial photography), so there is no reason why they cannot perform to a similar standard.

NigelM

[E621Keith]

Not to mention the smaller chip size on the compact will see much less off axis aberration than a DSLR with a large APS size sensor.

[ollypenrice]

Or if you want to go up market on the fast frame route there's the range from The Imaging Source. They really are great cameras.

Olly