To be honest, I think your best buy would be the Skywatcher 120 Esprit. It's a good price with good optics and you will get many years of use out of it before you think you need to upgrade. If you can afford it, get the TSA120 although as a beginner it will be a long time before you can discern the difference between the 2.
and what about the explore scientific fcd 100 127 mm?
the esprit are good because the flattener, but what about the explore scientific? it have fcd100 glass...
ES isn't nearly as good as the Skywatcher Esprit.
You also need to figure out which equatorial mount you will buy before selecting a telescope.
A Celestron Advanced VX or Skywatcxher HEQ5 would be OK with an Esprit 80 for example.
If you want the Esprit 120 you need a heavier duty mount such as the Skywatcher AZ-EQ6 or maybe Vixen SXP(if money isn't an issue).
Most people start out with lesser gear and work their way up to the point at which they are content.
I'm a casual/beginner imager but I have no intention of going beyond my Advanced VX and 4" Apo (Televue NP101is) along with a Nikon D5600 DSLR. If youy want to go the whole hog you'll need better gear, but you need to crawl before you can learn to walk.
The most important piece of your Astro gear should be your mount. A good mount will allow good images with average gear (telescope/camera) but an expensive telescope and camera will struggle on an average mount.
im thinking to buy the ioptron ieq45 pro equatorial mount and nikon d810a as my main imaging camera... and after this conversation i think i will go with the esprit 120? or with the esprit 150 if there is a focal reducer... if there is not i think i will buy the 120..
The most important piece of your Astro gear should be your mount. A good mount will allow good images with average gear (telescope/camera) but an expensive telescope and camera will struggle on an average mount.
I dont't think an Ioptron IEQ45 is nearly enough mount for an Esprit 150. It's rated at 45 pounds while the Esprit + camera + guidescope + guidecamera + finder etc would exceed this.