p208 final conclusion

After all the fiddling, dismantling, blackening and sticky velvet, I realised that the only optical train item I didn't test was the dew shield. Blackening its inside produced the same curved -and very difficult to remove- artefacts. Let's see what happens without.

At last we have something which is easy to process without having to jump through hoops curved artefacts.

I'll let the raw stacks speak for themselves See also here.

with dew shield 

without dew shield