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Disappointed with DSO views? I have the answer!


Bazzaar

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Still cant make my mind up If I should get a 1/3" sensor cam just to try it out or wait a bit longer and go for a 1/2" one..

The 1/2" one has the same number of pixels and (on paper) seems less sensitive than the cheaper 1/3" one. I'm struggling to see the benefit over simply using a more aggressive focal reducer.

Any comments anyone?

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I am interested in whether anyone can explain the Day and Night setup on these cameras. [...] From what I can gather the ICR methods works by sensing when light is poor and mechanically moves the IR filter out of the way and switches to b&w - when the Day and Night setting is auto (as opposed to Day or Night). The electrical system appears to work by having a fixed IR filter but changes AE settings in low light.

I think the only difference is that one system doesn't physically remove the IR filter in B&W mode (and is thus unsuitable for use under IR security lighting) Other than that I thought they were the same. Just my presumption though.

If the ICR method involves shifting the filter out the way in low light why bother with physically removing the filter?

'cos the filter is only shifted in B&W mode, not colour.

On a more fundamental note - can anyone explain why it is recommended that the built-in filter is removed but replaced with a high-quality UV/IR filter on the nosepiece?

The inbuilt one is believed to be too aggressive, losing Ha light. I also believe that you don't need an IR filter at all if using a reflector telescope.

Again, the above just my presumption and I'm sure someone will correct me if I am wrong...

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The 1/2" one has the same number of pixels and (on paper) seems less sensitive than the cheaper 1/3" one. I'm struggling to see the benefit over simply using a more aggressive focal reducer.

Any comments anyone?

I have both. (I have the A2333, SCD435 and two SCB2000)

The 1/2 inch version is better by quite a bit.

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'cos the filter is only shifted in B&W mode, not colour.

Thanks all for the responses.

I spoke to Samsung this morning about this and it appears to work as follows:

Day/Night setting = 'Colour', shoots in colour with filter in place

Day/Night setting = 'B&W' shoots in b&w with filter removed

Day/Night setting = 'Auto' switches between the two according to light levels.

As far as I can see this means that for astro purposes if you are happy shooting in b&w then set to 'Auto' and the filter will be removed in low light so no need to open the camera and physically remove the filter.

Shooting in colour will only happen when Day/Night = 'Colour' or when Day/Night = 'Auto' and lighting is good, i.e. daytime. In both cases the filter will be in place. Physically removing the filter does not automatically make the camera shoot in colour.

It seems that the only way to get colour shooting in night conditions (if that is what you really want) is to set Day/Night to 'Colour' and physically remove the filter.

NB The Samsung person I spoke to seemed quite knowledgeable and he also consulted a more senior colleague but I'm guessing they were only 95% sure of this because I was asking about functionality that is specifically excluded from the camera design and which they had not considered before. But it seemed logical to me.

This applies to the Day/Night (ICR) cameras as opposed to the Day/Night (electrical) cameras (in which the filter is locked in place). However, I think the principle is the same on both, i.e. if you want colour, set Day/Night = 'Colour' (to prevent b&w AE settings being made) and physically remove the filter.

Edit - got the terminology wrong (Day/Night instead of Colour/B&W) and this really just confirms what great_bear said in one line!

Edit - there is a youtube video showing settings for the SCB-4000 which sets Day/Night to 'Auto'. I can only assume that this means the operator is happy to use B&W at night time (in which case filter removal would be unnecessary).

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Hi

PAL version has more pixels:-

752x582 PAL (437664 pixels)

768x494 NTSC (379392 pixels)

The actual resolution you get will depend upon your capture device and how good the colour decoder is.

Because it 50hz not 60Hz you can get a longer integration time with the PAL version:-

x512= 10.24 seconds PAL

x512= 8.53 seconds NTSC

Samsung claim the same sensitivity for both versions

Hope this helps

Paul

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Thanks for the info. Paul, that makes approx 15% more pixels for the PAL version with approx an extra 20% in stacking time.

I'm guessing that it would be hard to tell the difference, although I'd be interested to hear what anyone else thinks.

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Ok so i'm going to get a camera....but need something cleared up

which is the better camera?

Samsung SCB-4000P or the SCC-A2333P

post #132 quotes that the 4000P is the newer model but its min light level is higher than the A2333P and it costs £20 less. Does this min light level make that much difference, i really just want to know which is the better camera. :BangHead:

Thks

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I cant believe I missed this thread:icon_confused: Should have chipped in sooner but the brains been otherwise engaged lately.

As John said earlier on, I was on the pitch next to him at SGL6 with my Meade 127EDT and a Mintron 12V6 feeding into my netbook via an el cheapo capture dongle I got off ebay. This worked well and together with Skymap running the goto on the mount I was able to bag loads of obscure galaxies that would otherwise have been out of range of a 5" refractor.

I started several years ago with a Mintron 12V1 in a C11 and this was gob smacking for pulling in the fainter DSOs. I also tried a Watec 120 with the C11 and will always remember the view "live" of M33, it was all there:icon_eek: arms, Ha regions everything, fantastic.

I prefer the views I get with a little B+W 5" Maplins telly to those on the netbook or lappy because you have so much more control on contrast and brightness with the crt than lcd but thats just my preference.

The newer 12V6 is the same chip size as the 12V1 (Sony Superhad chip) but with alot better noise control, nice black background with little ampglow and fewer hot pixels.

I only occassionally image with it for record purposes only, I have an Atik 314L for real imaging, the camera is mainly used for enhanced visual work.

The Watec is much more sensitive than the Mintron agreed but the Mintron is about half the price so dont discount this camera if your looking to go video.

Oh, I used to autoguide using the mintron as a very capable guide cam, now thats one versatile little camera:)

Ive no experience with teh Samsung cams but from what I have seen in reviews they are just teh ticket, sensitive and cheap.

Finally, video astronomy has been round for yonks, I started about 7 years ago and always wondered why other folk didnt do it.

I suspect a lot of people class it as an impatient persons imaging method but it shouldnt be classed with imaging, (even though you can image with it) its an observational tool 1st and foremost IMHO.

Thankfully its recently started to get the attention it deserves, long may it increase in popularity.

Philj

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Ok so I'm going to get a camera....but Samsung SCB-4000P or the SCC-A2333P

Don't forget the sdc-435 (scb-2000) unless you are specifically after the 1/2" sensor.

Looking at the technical data sheets is a pain as they are formatted differently and are not consistent but if you are bored then open up a browser and tab between these (ctrl+page up/page down):

http://buythis.co.uk/pdf/5155.pdf

http://buythis.co.uk/pdf/5094.pdf

http://buythis.co.uk/pdf/4969.pdf

scb-4000

Colour: 0.1 lux (50 IRE @ f1.2), 0.0002 lux (Sens-up, 512x)

B/W: 0.01 lux (50 IRE @ f1.2)

scc-A2333

Colour: 0.12 lux (50 IRE @ f1.2), 0.000006 lux @ 15 IRE (Sens-up, 512)

B&W: 0.012 lux (50 IRE @ f1.2), 0.0000006 lux @ 15 IRE (Sens-up, 512)

sdc-435

Colour: 0.05 lux (50 IRE @ f1.2), 0.0001 lux (Sens-up, 512)

Without knowing at what IRE level the lux figure is quoted at it’s impossible to compare figures. So the 15 IRE figure for the scc-A2333 may not be better than on the other cameras it's just not stated on the other cameras.

Where the IRE values can be compared then it looks like the minimum illumination figures are the same for the scb-4000 and scc-A2333P and slightly better for the sdc-435.

Signal to noise ratio is quoted at 52db's for the scd-435 & scb-4000 and 50db for the scc-A2333P. (higher is better).

I’m sure there will be other factors that make a bigger difference in the real world performance, maybe someone who has them both can comment.

A note about IRE levels - without knowing at what IRE level the lux figure is quoted at it’s pointless in comparing figures. The Institute of Radio Engineers came up with the term IRE to represent the composite video signal in percentage terms i.e. 100 IRE equals 100%, a full (good) signal. 50 IRE means it has only half original signal and 15 IRE means 15% of original amplitude. So a reading without defining IRE level is pretty useless.

sbc-4000 has a discrepancy on the colour Sens-up - It says 0.00002 lux (Sens-up, 512) on the product page but 0.0002 lux (Sens-up, 512) on the data sheet.

Good luck, it's a nightmare comparing spec's.

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