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M42 with the TMB and Artemis 11002

roundycat

By roundycat
in Imaging - Deep Sky

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roundycat

roundycat

Posted
Posted

Hi all,

as the title says this is basically a quick grab shot whilst waiting for M81/82 to show up. 20m each of RG and B in 5m subs. I used my TMB 152 with the Artemis knowing it would not be a good match, the TMB doesn't cover such a large chip at prime focus. Also I did not have any flats for this combination so the corners are vignetted more than they should be. I put a border around the usable part of the frame, it gives me 3300 x 2300 pixels so should make for some fine A4 prints.

Dennis

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narrowbandpaul

narrowbandpaul

Posted
Posted

thats a very nice image Dennis.

the whole frame looks OK to me, but I know TMB dont have flat fields over a huge sensor like that.

Is a dedicated flattener available? if it is , I would think it mightily expensive.

But sweet scope. Havent used the 152 but have used the 130

keep these images coming

paul

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Eddie

Eddie

Posted
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Great quick grab Dennis :(

Though, I do reckon there is more in there to be pulled out, hope you don't mind but I had a quick play with the JPEG.

Paul, there is a dedicated flattener available, but your looking at about £700-£800!!

Eddie

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Mike W

Mike W

Posted
Posted

Nice image Dennis, I can`t get over the quality of the images being produced in the back garden, 10 years ago you would be looking at the quality of this sort of thing being done at a major observatory. keep up the good work.....great stuff.

Mike

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roundycat

roundycat

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thanks guys. Eddie, I deliberately did not bother to pull out any more detail as this really was a waste of time. My real target, having changed scopes was M81/2 something that sits in the TMB/Art field quite nicely. If I set about M42 with this combination of scope/camera I would go for a portrait orientation and collect the Running Man as well.

By the way, the reason I don't own a flattener for the TMB is that Telescope House told me it would be about £1000, if I could get one. The stars in the pic above are fairly sharp closer to the corners than my white border. With proper flats I bet I could squeeze a bit more.

Dennis

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Eddie

Eddie

Posted
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£1000 for a flattener is a lot of money.....in anyones books.

and the stars look quite good toward the edge.

Certainly is!

Dennis you could probably correct for this amount of curvature with the lens correction tool in PS (if you have CS2+)

Eddie

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Psychobilly

Psychobilly

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Yes £1000 is well £1000 but how much did the scope cost how much did the ccd cost...... so surely the cost of the flattner should be budgeted in if a flat wide field is what your after?

I am sure there a lot of people who would love to have these sorts of budgets to spend on kit for a "hobby"

which in the UK you seem to be able to part take in on a handful of nights a year...

Billy...

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roundycat

roundycat

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Rob, just a quick note to you as you have just bought a 'proper' scope. It is foggy tonight so I have been messing with flats with the TMB Artemis and the good news is the rough flats I took take out most of the vignette so the 35mm frames is usuable right up to the corners. The stars are not that bad there either.

Dennis

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GordonH

GordonH

Posted
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thanks guys. Eddie, I deliberately did not bother to pull out any more detail as this really was a waste of time. My real target, having changed scopes was M81/2 something that sits in the TMB/Art field quite nicely. If I set about M42 with this combination of scope/camera I would go for a portrait orientation and collect the Running Man as well.

By the way, the reason I don't own a flattener for the TMB is that Telescope House told me it would be about £1000, if I could get one. The stars in the pic above are fairly sharp closer to the corners than my white border. With proper flats I bet I could squeeze a bit more.

Dennis

Hi Dennis

Try going direct to APM telescopes in Germany, they do dedicated field flatteners for the TMB scopes, I got mine for my TMB 115 and it cost about £790. With it you will be able to cover the full chip of your camera but make sure you get the necessary spacing adapters as well. I take it you are using 3.5 inch focuser with your TMB. Since using this flattener with my H36 I get no vignetting and it covers the whole chip perfectly

Best wishes

Gordon

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roundycat

roundycat

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My thanks to all of you guys for helping me to spend my money! Having just lashed out on the FSQ and contemplating a reducer for that I think that £800-1000 on the TMB can wait for the time being.

I was never going to use it with the Artemis until I saw the result above. Having taken some more flats and looked more closely at the corners I think it likely that I can get away with a bigger frame or smaller crop. If the fog, mist and rain ever clear up I will point it at a star field and try again, if the result prints ok to A3 the TMB reducer can go take a jump!

Dennis

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