dark current noise

Astrotripper wrote:

alexisgreat wrote:

The EM-5 weighs 15 oz, while it doesn't sound like a huge difference, on a single armed Nexstar 8 SE mount that can make a different, dont you think?

No idea. It looks big and sturdy, so should probably handle it.

Even my E-520 seems a bit large to me, but I just got my E-PL6 and it looks really small, I am pressing the buttons with my finger nail rather than my finger lol. I just hope nothing on this camera is fragile and prone to break.

The camera has an IR blocker in the front doesn't it to protect the sensor from dust when you change the lens?

I have dew strips and a dew heater for everything from my 8" telescope to 60mm refractor to 1.25" eyepieces. Can I use the dew heater and dew strips on the camera-lens combo when it is not attached to the telescope in lieu of getting a weatherproof body? Hopefully that would work.

It's a good idea for sure. I've had some star-trails and night time-lapse sessions ruined by dew fogging my lens. It won't replace weather sealing, but you can always cover up the camera itself with something so it would not get wet.

and can use an ac adapter as an alternate power source

That's nice, I was not aware of that possibility. But you could still make your own solution for that problem, as described here by another forum member.

Excellent, so there's a solution to making an alternate power source for the E-PL series of cameras?

I'm guessing a similar thing can be done for any camera, really. But I'm not really good at stuff like this, can't even say how hard/easy that would be.

In that thread he mentioned USB "power packs" I'm really curious about what that might be.

Now, if you would like to do wide field astrophotography without a telescope, just with a lens, then a weather sealed camera and lens can be a big deal.

Wide starfield astrophotography is a major interest for me, but I'm wondering if using dew heaters and heated dew strips can make getting a weather sealed body or lens unnecessary.

You can get by with it if you're careful.

I wrote this in another thread regarding high ISO/long exposure noise but your idea of making an alternate power source got me thinking......When will major camera manufacturers wake up and offer at least optional TEC cooling for all non-point and shoot cameras? It is simply done and will cause a major reduction in noise. Maybe we can make it ourselves and provide cooling for our cameras to reduce noise even further (especially at higher temps- I am specifically thinking of imaging in the summer when it is in the 70s here all night.)

It simply makes no sense for consumer cameras. And especially for Olympus, that has sensor floating around in the assembly. How do you efficiently cool something that you cannot make contact with? And where do you get the power to cool it? And how do you get the excessive heat out of the camera. And what good is all this for an intended user of the camera?No, it's simply not feasible, and the payoff is simply not worth it.

The proper solution is to follow the trend that takes place in mobile electronics. Smaller, faster, more efficient, more integrated chips that drain less power and produce less heat. Instead of cooling, try to produce less heat.

I'm not really sure how easy it is to do but on Cloudy Nights and Astromart I've seen '"modded" DSLR on sale from time to time that the previous owner made TEC cooling for. I never actually did it myself but when I corresponded with the people who made it they said it was relatively easy. One problem they did mention though is that you have to be careful about dew- when you cool a camera down it becomes more prone to dew- so they did what is known as regulated cooling.