JCIdaho

Thanks. I don't think I have the 55mm backfocus sorted, so will try that! Thanks!

Hello All! I'm completely new to AP and here to post my first pic! I followed Adam Blocks' excellent fast track tutorial on PixInsight. I have the follow equipment: StellaMira 90mm ED Triplet f/6 StellaMira 2" 0.8x Reducer / Field Flattener ZWO ASI 2600MC-PRO CGEM II ZWO Mini Guide Scope ZWO ASI 120MM Mini AisAir Plus I was able to take these images of M51 and M101, which I'm very happy with as a first attempt! I would love any feedback on those! Things I could improve on. I do have the following newbie questions (please direct me elsewhere if this part of the forum isn't adequate): 1) Gradients in images: I have quite a big gradient - you can see the blueish band near the bottom, then a green-ish band. I'd like to ask, is this normal? I understand I can (and have to a degree) process it away using DynamicBackgroundExtraction, but it feels quite pronounced.... is there something else going on that I'm doing wrong? For example see this pic, that I have just auto-stretched: 2) Image not flattened. I'm using a Field Flattener, but if you see in the image above, the stars nearer the sides of the image are warped / stretched. Again, should I expect this? If I were to take an image of a FoV filling object, like M31, then presumably this would have a large negative impact on the overall image? 3) Flats I'm using AsiAir to generate my flats. The generated preview JPGs look pretty scary, with the ring below. But then the actual downloaded files look much better. Preview Is there anything to worry about here? Testing around today, I made the following flat that looks awful from the AsiAir preview image, but I was able to get a spec of something off the sensor, to make it go away. Again though, the actual resulting flat image looks OK. Probably nothing to worry about, but thought I'd check. It's all new to me! Thanks.