Messier 35 an open cluster located in constellation Gemini. The cluster is approximately 2800 light-year far from Earth and it contains roughly 200 stars.
Second open cluster NGC 2158 is located in the background (upper right part of the picture). I didn’t know that there is another cluster in field of view. If I would know it, I would change the composition of the picture.
This cluster was the last one out of four captured during single night. In the early morning I slewed to M35 and went to sleep. The camera captured 56 exposures, 3 minutes each, before the dawn arrived. This means nearly 3 hours of total exposure time.
Technical details:
Telescope | Newton 254/1000 mm |
Aperture | 254 mm |
Focal length | 1000 mm |
Mount | Gemini G53f |
Autoguiding | ZWO 174MM, TS 60/240 mm |
Camera | ZWO 071 Pro @-20°C |
Corrector | TS-Optics 2" 3-element MaxField |
Filters | Hutech IDAS LPS-D2 |
Exposure | 56x180s, Gain 94, bin 1x1, |
Date | 2018-11-18 |
hi jakub i found your images whilst looking for images taken using the IDAS D2 LPS filter which i am thinking of getting ,which version are you using the clip type or the 2″ version, how do you find it, have you come across any issues with it ?artefacts /colour issues and are you using it in an area with LED street lights .
nice imaging btw jakub
Dear David, sorry for my late reply, but I had long time limited access to the internet. I use 2″ version, which is screwed between the camera and the corrector, as close to the sensor as possible. There are mainly sodium lamps on the streets, but recently they started to install also LEDs, therefore the light pollution is combined. SQM in my area is horrible – 19.8, but at one o’clock at night they switch off most of the street lamps and SQM goes up to 20.4, which is still not perfect, but quite OK. Maybe if I find the time, I can do a test and take 1 hour of integration time of some nebula with this filter and 1 hour just with IR/UV cut filter and compare the results. It would show us how much the filter helps. However, in December I got only one night without the clouds, so nature has to cooperate as well.
It has only one disadvantage – white balance is strongly green dominant and it cannot be adjusted to white neutral during capturing. This can be easily solved by post processing in Pixinsight. I simply calibrate and debayer the pictures, then decompose to RGB channels and apply linear fit.