Leo Triplet – DROGENBERG

3rd March 201910th March 2019

Leo Triplet / Esprit 120 F7 / Nikon D750

Leo_Triplet 24039 seconds or _6h40m_Nikon_D750_800ISO_Esprit120_F7_V1 66% JPG Nights of 24-25-26 February 2019 The start of the todal stream of NGC3628 is visible.

1st March 20191st March 2019

To dither or not to dither?

I have two similar sessions on the galaxy NGC3628, the ‘dimmer’ member of the Leo Triplet. One session was done without dithering, the second session with dithering. So maybe it’s educational to really compare the two results and verify what the effect is of dithering?

NGC3628 36x300S 800ISO Nikon D750 Esprit 120mm F7 NON DITHERED

NGC3628 54x300S 800ISO Nikon D750 Esprit 120mm F7 Dithered

The difference in background noise should be clear.

To be complete: the dithered image was 54x300s or 4hrs 30m exposure, while the non-dithered image was only 36x300s or 3 hours of exposure. Both nights were equal in quality.

27th February 201927th February 2019

An intermediate NGC3628

This galaxy is the third member of the Leo triplet. During the last nights I could image this with the Esprit120mm and the ASI183MM Pro. This intermediate result is L-filter 6hr36m of data processed in APP and cropped. Best seen by clicking on the image!

*NGC3628 ASI183mm Pro + Esprit 120mm + SW Flattener + No Reducer, No Filter*

And below is the equivalent image taken with the Nikon D750 DSLR. I had a lot of noise in this 3hrs picture (36x300s), I suspect something went wrong with the dithering. The tidal stream is just visible.