Ha-OIII tarantula

[allan gould]

I wanted to see if I could do narrowband imaging with my 20D during full moon and light pollution of brisbane and also see if I could synthesise the missing 'green' colour using Carboni's tools. Bear in mind this is just a very quick exercise to see if it was possible. The Ha filter I used is the Lumicon Ha which does NOT have an IR cut off and thus with the filter in the 20D gives about a 30nm bandwith. The OIII filter was a Baader filter. I did 3x300 sec exposures for each filter - obviously not enough data for a serious photo and took no darks at all or flat frames etc. Imported the stacked frames into PS and aligned them and then synthesised the other chanel. Its obvious that a colour shot can be done using just 2 filters and the light pollution easily combated. The photos were taken with a WO 80mm Apo.

[Tandum]

Allan, is your 20D standard or has the IR filter been replaced? I've been thinking lately that narrowband imaging is the way to go in the city.

[Hagar]

Hi Allan, Nice load of detail but the JPG compression artifacts are a killer.
Would have been better using the QHY8.. Come on christen it.

[allan gould]

Its a modded 20D and so should be equivalent to the QHY8 except for the cooling and dark frame capability. This was an experiment prior to doing some serious shots with the QHY8

[Tandum]

Cheers Allan, There's hope for my backyard images yet :)

[ozstockman]

Great picture Allan. I'm sure you'll get much better result with QHY8. I have been taking pictures of Tarantula for the last three sessions with QHY8 and VC200L(reduced to f/6) just to try my new setup. However I wasn't lucky in terms of weather and got one shot from each session. The only disadvantage of QHY8 is that you will need at least 8-10 mins for each frame to get all details.

cheers,

Mike

[Gama]

Allan, your biggest problem with the 20D is noise, but the QHY-8 or any Sony sensored camera doesnt suffer from it, so long exposures do not show any real noise problems, unlike DSLR cameras. If you read and looked at the images from the review of the QHY-8 by Clyve (Alchemy), you can see what differences there are between the 2 exposures.

Theo

[allan gould]

Theo
Fully agree with you. I was testing the filters rather than the cameras to see if I could do some pseudo-narrow band colour imaging. Thats why I took no darks etc. I just wanted a rough guide with a 'standard' luminosity object. The qhy may be tested out this weekend - Ws permitting (Wife, weather, wind etc)
Allan