Xplode

I've been very happy just using my mono 6D so i forgot to check this thread lately

I thought i'd share some results from the camera...

This is a single 120s @ iso 1600 frame from my mono 6D, flatfielded (with wrong flats) and stretched a little. Sensor temp was around +10C

Scope is a 12" f/3.8 newtonian.

It's the full uncropped frame so feel free to download and examine.

90x of those frames...dithered, no darks and old flats that didn't remove dustmotes.

Older RGB data with an 8" newtonian and 6Da.

Combined they look like this...

With some further processing by Göran Nilsson it ended up like this.

Pretty good results from what some CCD guys would call a "crappy noisy DSLR"

Great image Herra!

I'm doing my first real test of my monochrome 6D just now, 10min on the heart nebula with 7nm Ha filter with my 100Q. It's a little to warm so pics have more noise than i would have liked...not sure how it will end up after 2-3 hours imaging time.

Narrowband and Luminance is what it will be used for.

I have thought about sending it off to CentralDS in South Korea to get cooling on it, but not sure if it's worth it as it's pretty cold in Norway anyway during astronomy season.

Not a DIY job, but it's still a debayered DSLR so i hope i won't get thrown out of this thread

Last year i had an idea about buying a 6D and get it debayered, around new year there were a special offer for the Canon 6D (N) (N means without wifi and GPS) with a price of 20% under the regular model and on top of that a drawing board that was worth a good amount.

The special offer made the camera cheap compared to a regular one so i decided to go ahead and buy one to get it modified. The drawing board was sold for ~20% of the cost of the camera.

I sent the camera off to Brent Oliver (Hypercams and Mods) in the US that has debayered Canon cameras with great success.

Unfortunately the conversion took a very long time because he recently had a baby (and he also has a kid from before) and there was also some problems with Baader filters that weren't perfect (they had streaks that he couldn't remove by cleaning) so it took almost 7 months from i sent the camera to i got it back, today i finally got it! 

This is probably the worlds first 6Dm (monochrome)

Brend did a very good job and  autofocus works perfectly and there's very little left on the edges so it can be used for regular photography perfectly fine.

I have made some testshots and picked the best one that was of my cat sitting outside.

I opened in RAWTherapee and saved without debayering.

Resized to 25% and not cropped.

RAW file on Dropbox

What you require is a low profile M48 to Nikon mount adaptor like this

http://www.teleskop-express.de/shop/product_info.php/info/p6527_TS-Optic-ultrashort-Adapter-from-M48-to-Canon-EOS-EF-Bayonet---only-1-mm-optical-l.html

....but for Nikon.  I found one but can't for life of me find a link for it!

EDIT- the other possibility is a coma corrector with longer back focus distance like the  Baader RCC 1 Newtonian Coma Corrector

http://www.teleskop-express.de/shop/product_info.php/info/p6527_TS-Optic-ultrashort-Adapter-from-M48-to-Canon-EOS-EF-Bayonet---only-1-mm-optical-l.html

A low profile M48 isn't possible for Nikon because of the smaller flange, it seems to be barely large enough for a low profile M42 at 44mm throat. Canon has 54mm throat.

Thanks for that.

I've been told that the currently available range of OAGs an 55mm back focus coma correctors won't work - even with a "zero" width mk48 adaptor

I'm looking into the RCC - although I have found a number of threads where people describle problems they have had with its sensitivity to sensor alignment / tube flex.

I hope to pick up a set of new Losmandy tube rings that are designed to work with my Orion Short-Tube 80 guide scope to hold the orion guide camera in firm alignment. I'm hoping that this will reduce my differential flex issues enough that I can live without an OAG.

You are correct that a Nikon won't fit an OAG at all with with a 55mm backfocus.

Canon would work with a TS slim OAG, but a Nikon allows 1.5mm less distance between the flange and coma corrector so there is just no space.

If you want this to work you should get a Canon camera...they are much more flexible for astronomy and will cause much less frustration

Numbers for newtonians seems weird, for 30% obstruction contrast increases with bigges scoper as you would expect, with 25% obstruction the 250mm has better numbers than the 300mm which seems weird to me

Thanks for sharing the RAW files.

They open perfectly in Pixinsight with the option "create RAW bayer CFA image"  (dcraw -4 -o 0 -D)

Great. 

Could you also take a flat and post it as RAW?

If anyone is interested, here is a link to the full-size image. The image in my first post is uncropped but downsized and jpegged. This is the RAW file that has only been run through DCRAW with the -d, -6 and -T switches. Those switches force no demosaicing, 16-bit output to a TIFF file respectively.

http://www.timsroadster.com/pics/mono.tiff

Tim

I see there is still a bayer pattern in that image with uneven values for the pixels, i wonder how that would be fixed best?

I tried to debayer the image and it turns out looking good, but i guess resolution is lost in the debayering process.

Is there a way to change the pixels values so they get the correct values so it doesn't have to be debayered? Could DCRAW fix this or do they need to be processed by some new software?

500x500 crop from original image

VNG debayered by pixinsight

Changed to grayscale (extract luminance seems to give exactly the same result)

Could you post the RAW file so i could experiment more?

Guide speed works together with calibration step so 1850ms should work.

I did the calculations for your setup at 0.1x speed and calibration step would need to be 9200ms! I guess this is why your earlier settings didn't work.

Auto select star should work great, never had a problem with it myself so i suggest you stick to it too.

From what i understand hysteresis on DEC should only be used on mounts without backlash...so none of the Skywatcher mounts and most other cheap mounts won't be suitable either.

Firsly you need to check your guide speed. If you use EQMOD with pulseguiding i suggest you set it to 0.5x under "ASCOM pulseguide settings) in eqmod. If you use ST4 you also have an option there to set it to 0.5x. I have tried lower settings, but found calibration to take more time without making guiding more accurate.

I calculated your needed calibribration step to 1850ms.

I also suggest you change dec algorithm to resist switch.

SNR 40-50 seems very high? I usually guide at stars with SNR 7-12

I can confirm that i have the same problem as Olly with uneven backlash. Will contact the Norwegian dealer about it see what they say. I'll try the mount for a while to see if there's any issues from my mount when imaging.

My mount is probably from the same batch as yours Olly so i think i have those 3 access screws. Will take a look at the adjustment later today if i get that PDF from Ray.

Olly will need a larger scope to use the Gaia CCD, it has a total of 106 CCD's with a size of 6cm x 4.7cm each, resolution is 4500x1966 pixels.

Total size of the array is around 0.5m x 1m with a total of 938 MP.

Total area of the array is 2.8m2

Nice setup Olly

It will be interesting how you find the mount when you get it up and running.

I should have my EQ8 running in a few days, need to make a pier to mount it in the astronomy clubs observatory first

It's highly probable that some Tak's will be used on my mount too, a friend has FC60-QB, Sky90, TSA102, FSQ106-ED, TOA150 and Mewlon 210 which needs some imaging time 

Great looking scopes this new Esprit's 

I was gonna buy a Esprit 100 myself, but chose a TS 100mm quadruplet instead to avoid the problems with focal reducer distance and to be able to use filter wheel and OAG on a DSLR without problems if i want to.

Sorry to read about the confusion on focal reducer distance 

My first DSO was M51 taken on 22 March 2012.

Canon EOS 5D MKII (unmodded), Meade LX200 Classic 16", autoguided with PHD/QHY5, 600s exposure @ ISO 1600.

No editing other than darkframe.

Taken at my astronomy clubs observatory at Hågår, Norway