Context :

Aims : Clusters of stars are key objects for the study of the dynamical and chemical evolution of the Galaxy and its neighbors .
In particular chemical composition is obtained from different kinds of stars ( hot main-sequence stars , cool main-sequence stars , horizontal-branch stars , RGB stars ) using different methodologies .
Our aim is to apply these methodologies to the stars of the Open Cluster NGC 6475 .
Obtaining a census of the most important elements we will be able to test their consistence .
We finally want to establish more robust fundamental parameters for this cluster .

Methods : We selected high S/N high resolution spectra of 7 stars of the Open Cluster NGC 6475 from the ESO database covering the T _ { eff } range 4500-10000 K and of luminosity class V ( dwarf ) and III ( giants ) .
We determined the chemical abundances of several elements .
For hot stars ( T _ { eff } > 9000 K ) we applied the Balmer Lines fitting method to obtained atmospheric parameters .
For cool stars ( T _ { eff } < 6500 K ) we used the FeI/II abundance equilibrium method .
For the two groups of stars the use of different line-lists was mandatory .
LTE approximation was used .
For elements affected by NLTE deviation ( C , N , O , Na , Mg ) corrections were applied .
The abundance of many elements were obtained from the measurement of the equivalent width of spectral lines .
For those elements for which only blended lines were available ( O , He ) comparison of real spectrum with synthetic ones was used .
Hyperfine structure was taken in account for V and Ba .

Results : First of all we showed that the two methodologies we used give abundances which are in agreement within the errors .
This implies that no appreciable relative systematic effects are present for the derived chemical content of cool and hot stars .
On the other hand giants stars show clear chemical peculiarities with respect the dwarf concerning light elements ( up to Si ) and maybe Ba .
This fact can be explained as an evolutionary effect .
Then , having a new estimation of the metallicity for the cluster ( [ Fe/H ] =+0.03 \pm 0.02 , [ \alpha /Fe ] =-0.06 \pm 0.02 ) we fitted suitable isochrones to the CMD of the cluster obtaining the basic parameters ( E ( B-V ) =0.08 \pm 0.02 , ( m-M ) _ { 0 } =7.65 \pm 0.05 , Age=200 \pm 50 ) .

Conclusions :