pixueto

Yes, I had that problem too I'm not using epoxy anymore. The filter frame sans filters works fine.

Indeed, the filter frame naked works nicely protecting the golden connectors when removing the CFA. I've just removed the CFA in the fringes of my 1000D sensor.

Also for the knowledge database . This is what I've learnt from my humble experiments and those of the intrepid pioneers in the forum:

1. The sensor cover glass removal is a pain in every camera model apart from the Canon 1000D and 450D. It can only be removed intact in those two models.

2. The use of epoxy to protect the golden connectors or the heat to remove the glass is indeed a very bad idea and with all likelihood it will destroy or damage the sensor -the epoxy may take a while before the harm can be noticed, though.

3. In the canon models, the CFA in the 350D is the easiest to remove without scratching badly the sensor. Some people like Luis are getting very good at this. However, the wooden tool and the mechanical procedure is needed.

4. Dichlormethane doesn't seem to work with the canon models.

5. The sensor, once debayered, even badly scratched and polished unevenly can work nicely and all defects can be fixed with control frames: flats.

6. Dichlormethane seems to work with the nikon CCD sensors; at least with the 40D. Thus, it's possible to completely debayer a sensor without leaving any scratches or CFA leftovers.

Now, I have a nikon D80 sensor. I'm going to apply Dichlormethane and see what happens. If the CFA can indeed be removed completely without any mechanical means, this may be the choice for a monofied astrocamera for me. The questions will be then, how good this nikon model es for astrophotography and how can the raw files be extracted without any demosicing being aplied by nikon software?

Anybody can shed some light on this? Any experience with the nokon D80 for astrophotography?

Thanks

And another entry for the knowledgebase (this thread ) -

Dichlormethane does a very good job on a dead D40 Sensor, dunno what went wrong with my last Sensors (CFA leftover).

Spray it on, wait one minute and easily clean the sensor scratch free with a Q-Tip.

My only problem is, the sensor died while applying epoxy to protect the wires

That's very good news indeed!

I have a nikon D80 sensor ready for the Dichlormethane treatment. Have you got any experience with that one?

Hi all,

I have some data now from the Mono modded 450D to compare with the Mono 350D, these two images were made on the same night and although the 450 is not cooled yet, I think is shows very good performance, gladly it shows very good sensitivity, more then my initial test were showing, so perhaps even with smaller pixels, the better processor and 14 bits are pulling that faint details on pair with the bigger pixels of the 350D, the image as a bit less signal but also a bit less total integration (7x7 min. vs 8x7 min. of the 350 image).

So bottom line is, the 450D WILL MAKE ONE HELL OF AN ASTRO CAMERA ONCE IT'S COOLED

So here is the 350D image (8x7 min. @ 800 ISO COOLED:

http://www.flickr.co...in/photostream/

And the 450D image (not cooled camera):

http://www.flickr.co...in/photostream/

Don't forget to right click and choose original size.

Cheers,

Luís

P.S. Way to go Gina!!!!!

That's brilliant Luis. So 7 minute subs is the way to go then? I went for 20 minute subs with my monochrome canon 1000D and the noise was horrendous. I did that because, with the 7nm H-alpha filter, the histogram was completely to the left but then when processed with IRIS, the stretching seemed to go well.

Now, if the image with the 450D is uncooled and the total integration time is 49 minutes, it seems to me that cooling isn't that critical after all, is it? I mean, very good results are being achieved at ambient temperature. Luis, can you tell us which control frames have you used in those photos?

Thanks

I have a feeling it has been mentioned - can't remember... I think it's the thermal gradient that breaks the bond so I guess it would work. But how woiuld you do it - what would you use? Liquid nitrogen?

I've been removing the rest of the glass from the sensor I've just destroyed - it took a lot of heat, far more than the sensor would have stood. Also far more than the one I was successful with. I think the bond on these varies from sample to sample.

I now have a sample sensor mechanical model that I can use to design the mechanics, sealing etc. of the super-cooled camera. I'm planning to include just the image side of the sensor plus the shutter and main frame in the dry enclosure and to protect the imaging board components with either potting resin or silicone grease or something of that sort. I'm hoping I can thermally insulate the rest of the camera components from the cold so that moisture doesn't condense on the electronics though a coat of water proofing wouldn't go amiss. I'll cover all this in another thread.

Gina, I think we were all doing very well until it has been decided to use heat and epoxy during the process. Unfortunately we all went backwards when that happened. I think best thing we can do is to find ways of breaking the glass covering the sensor without damaging it or else, go for the 1000D or 450D where the glass can indeed be removed in one piece.

I've been reading this thread occasionally for nearly a year but the end seems no nearer. Could someone summarise its success or otherwise here and elsewhere perhaps with some sample mono pics that demo its validity. TIA

This is my modest effort targeting the knot in the Heart nebula (inserted an internet colour picture of the nebula for comparison). Processed with IRIS (with the help of Luis). It's only three subs of 20 minutes each, 7 dark frames, 7 flat frames and 7 offset frames during a warm summer night. Next time I'll use a lot of shorter 8 minute subs (as suggested by Alistair), hopefully during a colder night and see if I can get rid of the thermal noise.

I've used a monochrome Canon 1000D with a 2" H-alpha filter (7nm). During the monochrome conversion, I scratched the sensor badly and unevenly and yet, no defects can be seen once the control frames have been included so the mod is very feasible indeed -in my opinion.

Hope that helps.

yes, Dichlormethane, which does a nice job if you have more patience than me

used the wooden tool after that, seems i didn't had a clean sensor, so it could be that glass particles got under the tool.

Thanks. Why did you feel you had to use the wooden tool? wasn't it enough with a microfiber after applying the solvent??

Is it difficult to remove the glass in a nikon D80? I'm waiting for a sensor to arrive and have a go.

Many thanks

Damn, i need more patience. Scraped toooo deep into the sensor... (NEX-3, only one pink picture).

But at least, my D80 is working. Oh, lets say, half working. scraped a bit blue frame, two dead rows. I think i haven't removed everything from the CFA, reading on one spot little different values from the colour channels.

To end my camera massacre, last two chances. Two defect D40 with working sensors are on their way, to get back to the camera, i started with.

Going the Dichlormethane route one more time, but now with more patience and less aggressive

Did you use Dichlormethane with the D80?

Cheers Alistair,

Thanks mate

Very happy with this

And happier to finally overcome the dredfull cover glass problem, yes you must get a small thin bladed x-acto and gently cut the glue all around the cover glass, just stick the blade point betwen the glass and sensor housing and take your time, you'll se some "threads" of glue once you pass the blade on the joint, apply some more presure at each pass and you'll see the glass becoming white as you pass the blade, eventually it will turn white all around and the glass will pop out, begin lifting the corners gently and start from there, don't force the corners though as they are the weak spot, too much and crack...

Yes, it's what I do the 350D mono for "L" and the 450D color for "RGB" then blend in PS...works great!

Cheers,

Luís

Congratulations on your mod Luis. If there are some scratches they don't seem to come up once you enter the control frames in IRIS as you tought me but it's nice to have as clear a sensor as possible.

As for the glass, I hate being the bearer of bad news but, according to my experience, the 450D has one of the easiest glasses over the sensor to remove -only the 1000D is easier. I reckon the 1100D and the 350D are different kind of beast. Has anybody managed to remove the glass intact in a 350D yet? I'm deciding when I should have a go at it inspired by your Eagle nebula H-alpha picture (wonderful). Still thinking whether or not I should apply heat to remove that glass!

In the meantime, I've ordered a nikon D80 sensor for £40 but it will take ages to arrive. I want to have a go with the solvent suggested by JTW. After all the work shown in this thread; your experiences and mine , I've decided that I'm going to have a go with the 350D and the nikon D80. I kind of suspected that the CFA on the 350D was the easiest to remove without scratching the sensor but this last information from Luis just confirms the 350D is the best choice.

Pixueto, this could serve as a guide for exposure lengths for uncooled mono dslr's.

• Take 2N-1 exposures of t_ORN/2 duration.
  

In other words, if you determine the sky limit exposure time t_ORN to be 10 minutes, instead of taking five 10-minute exposures and median combining, take ten 5-minute exposures and use the Sigma Clip combine method. And be sure to dither the exposures. This will result in excellent noise reduction from all possible sources (assuming you take a sufficient number of dark frames, and taking a flat field or three couldn't hurt).

http://starizona.com/acb/ccd/advtheoryexp.aspx

Thank you. What free software is there around for measuring the sky glow in the formula? If any.

yep I like this workflow as well but rather than using the chemical, why not try gina's method with ajax and the cleaner? seems to do a clean job. maybe you could use a soft wood tip rather than a sensor swab. the wood should soak up the liquid and dispense with slight pressure.

I'm very wary of applying chemicals which can get to the sensor. Maybe if some people experiment further with dead sensors... a mean, this project is getting expensive!!!

to be precise, i only use a spray which contains dichlormethane and some other additions.

its a very viscous spray, which is like foam after applied, so i spray it on the sensor and wait for a little time.

In my opinion, it could be that the leftovers react in the wrong way with the spray.

So that we have a small timeframe, in which we can remove everything, when we leave this timeframe, the CFA "hardens".

Contents of the spray, (from a german safety datasheet):

Dichloride 50%-100%

Propan 10-25%

Methanol 1-10%

Toluol 1-10%

What about this workflow then: remove the majority of the CFA with the wooden tool without applying too much pressure in order to avoid scratching the sensor. Then apply dichlormethane to remove the leftovers with just a q-tip or sensor swab.

Just a thought

Yes Gina but the problem with the 350D is the glass covering the sensor. Apparently, it's one of the hardest to remove -that's why I haven't started debayering mine.

Luis, have you managed to remove it intact in your last conversion?

One of the things I've learnt from my experience with the partially debayered 1000D and the 7nm 2" H-alpha filter is that I can't use live view. The image is too dim. Another reason for going right for the 350D.

However, I think we are focusing too much on not hitting the golden connectors but the fact remains that the difficulty is in removing the CFA, leaving the surface even and possibly without scratches. I think only Luis has managed to do that (twice) with a 350D. I have a feeling that this is something it can only be achieved with this model -or possibly one of those nikon DSLR with the CCD sensor? Anyway, Luis is now debayering a 450D so we'll see how that goes.

The problem in the 350D is to remove the glass on the sensor more or less intact but, if the epoxy was responsible for those sensor failures, maybe we can apply heat to remove the glass now?

there is one way you can protect the connectors.

Simply leave the frame where the filters are

When you are removing the array. I'm talking about the plastic

Where the filters are attached. Just leave it on top of the sensor

And you won't be able to see the golden connectors.

just a thought.

Alistair, here is the link to the original raw files you wanted to process:

https://www.dropbox.com/sh/knygb2tb7e9jky9/PAmW2n58wF

My Dichlormethane "Carbon and Paint Stripper" did a good work on my two Nikon D40 Sensors (both dead anyway, went too deep while scraping, the other got smashed removing the cover glass).

5 minutes after the application of the Dichlormethane, the CFA is really soft and much of it can be easy to remove with a q-tip.

BUT it leaves some traces of the CFA, which are not so easy to remove with a second application of dichlormethane or my cherrywood tool. (one possible explaination: the tool is used directly after the dichlormethane, so the wet wood does not scrape enough).

In my opinion, i don't get away so easily with just using Dichlormethane.

The Dichlormethane Method works also on the NEX-3 Sensor (CMOS), just tried it.

The Nikon D80 is the next in the row...

Thank you. How do you apply the dichlormethane?

Why would be so easy to remove most of the cfa with dichlormethane but not the leftovers? Any possible explanation?

Here is the link to the Tiff file from the stack of three lights (20 minutes each) with the H-alpha 7nm filter, ISO 800. In the stack there also are 9 flats, 9 bias and 9 darks.

https://www.dropbox.com/s/9mstmdpi9tbrk0y/NarrowbandTest.tif

Hello all,

Good to hear from you that are getting there with debayer, Gina very glad this one is working, keep it up! Pixueto, you're wellcome mate, that Ha image looks great to me, now you just need a cooling system to do very long subs with no noise

From my side, I made another 350D sensor, this time all went well, not a single scratch on this one, I used the wooden tool and a great deal of patience, still some very small particles to clean but as i'm doing also a TEC cooling system for this camera I will dismantle it again and give it a good clean up

Here goes "first light":

http://www.flickr.co...N08/9633235880/

Today I'm gonna try my luck on a 450D camera, I have some good friends that's are helping me out with this, some are willing to sacrifice their cameras to get a mono sensor...can't promisse anything though, we will see if I can do this one

Cheers,

Luís

Luis, could you please advise on the ISO and sub length you used for that wonderful photo of the Eagle nebula in H-alpha with your first debayered 350D?

Thanks

Just something for the knowledge database:

ATA scrubbing powder has a micron size of round about 50 micron.

Does a good job on the first layers of the CFA, but for polishing i would go for something more softer.

Got a hand on a NEX 3 and a Nikon D80.

I know the Nex3 from my Infrared Conversion.

<-- got mad, debayering everything with a APS-C Sensor, should get some positive results some time... to legitimate my actions.

What about the dichloroethane you were using before? Wouldn't that remove the CFA on the CCD sensor in the nikon 80D?

Alistair, are you sure you want to process those files? I mean, the noise in the 20 minute subs was horrendous. Also, they are each very big files! I'm showing you attached the jpeg files right from the camera. The camera has surely applied some demosicing but it will help you get an idea of the noise with the lights, darls and offset frames, as well as the state of the sensor with the flat frames.

However, I think IRIS dis a pretty good job and I'll be using it in the future. Thank you Luis.

Oh no! I'm so sorry Gina.

Hi Gina,

How exactly are you removing the CFA? are you using a scraping tool at all or is it the ajax on a cotton bud?

I'd suggest caution with the bud cause you could easily knick those wires cause its broad, and you won't be able to get to the edges.

as for removing the cover glass, yes you use pressure with a small screwdriver or blade inward slowly till it gets white right to the inside of the frame and you contnue around.

one of the guys in IIS took a 350D sensor, scraped away the edges of the glass, apparently that removed the glue at the sides, and then was able to remove the glass the same way, that is pressure inward till it turned white and removed the glass in one piece.

i think that's the first time anyone's taken off a 350d intact. but I might try that as well although I know the glue doesn't bleed off the glass edges.

with testing the sensor at various stages, isn't that risking the ribbon cable connectors? i flipped one on the 350d and the clip came off. couldn't put it back.

wish all the ribbon cables were the slide in type like the 600d.

good luck.

Alistair

Gina, Alistair is right. It isn't advisable to open your camera so many times. The black/brown plastic hinges locking the ribbon cables in place are very weak and they are prone to breaking when you release and lock the cables a few times.

Thank you Luis for your help with IRIS processing. I've eventually managed to process those images. I have processed three 20 minute subs (that's 60 mins total) with the debayered canon 1000D, the SW ED80 with focal reducer and a 7nm Baader 2'' H alpha filter. I've included 7 bias, 7 darks and 7 flat frames. This is the result. I'm new to all this narrowband thing so, I suppose the Tiff file could have been far better processed. I can leave a link to dropbox to those interested in stretching the file.

I went for the knot in the Heart nebula, as I wasn't sure if I would be able to frame the whole nebula with my partially debayered sensor.

Gina, I think the control frames have eliminated the imperfections in the sensor.

I would very much welcome your comments.