My first prints from my GH5 are a disaster! Where am I going wrong?

Danielvr wrote:

What I was doing was going to Lightroom and exporting the pictures to be printed on shiny thick paper.

STOP!

These book printers use equipment and automatic corrections carefully tuned and calibrated to make the best out of plain out-of-camera snapshots. Don't try to outsmart them - just process your raw files to full-size (!) JPGs that look good on screen and you should be fine. The photos won't look as bright as on your monitor because paper has a smaller dynamic range - but they should otherwise look very good.

Again, be sure to submit full-sized images - in the case of your 20MP camera I think that would be 5184 x 3888 pixels (smaller only if you have cropped them) - don't resize them and don't have them resized in exporting. From your description of what went wrong (grainy, no sharpness and definition) I suspect that this is where it went wrong. Maybe you can still return this book? Most suppliers seem to offer a satisfaction guarantee.

I shoot RAW.

I export jpegs.

images are then under wife's control.

We used to print in house more often than not but my wife has been using these online photo/book makers more and more in the past years.

she always tells 'them' not to make any adjustments to the images. Use as is.

apparently some print houses listen or are able to comply and others do not listen or are unable to comply.

by now she has her favourite print house or two. funny thing is from time to time she will recive a poor job from the same outfit that has done well with the last couple/few jobs.

I always say it must be new staff.

She complains and they send a new job and it's usually better.

the issue I usually see when she receives a bad job looks like a double print profile was applied more so than overzealous global enhancements.